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In the preceding document we had concluded our exposition about Extensionality. In the present document we continue our exposition (still largely following HOENEN, 1947) of the organic world's inorganic context as seen by the Aristotelian-Thomistic metaphysics as the latter is integrated into our Explicate / Implicate Order ontology. We will begin with the discussion of  Place and Space.

Much about Place, Space, Medium of localization, and the Aether of Lorentz has been written already in  Fourth Part of Website, part XXIX (Sequel 5).  ( If one prefers to have Fourth Part of Website including the left frame, click  HERE ).  Here, in present Part of Website, we'll do things more comprehensively, and take into account the latest developments of our theory of the Explicate / Implicate Orders, and especially study the distribution of extensionality and intensionality (extension and intension) over the two Orders :  Extensionality belongs to the province of the Explicate Order, while intensionality, and with it intensive qualities, belongs to the province of the Implicate Order. It is supposed (checked and investigated) that a  quality  of a thing presents itself in the Explicate Order(-part of the thing) in the form of some structural aspect of that thing, i.e. the quality is extensionally expressed there, while in the Implicate Order(-part of the thing) this same quality represents itself as an intensional feature, i.e. as a true intensive quality.
As an example, in the case of a color of a thing -- a supposedly true quality -- we have to do with a particular structural, and thus extensive feature of the thing, which as such is encoded by light waves having interacted with that structural feature, and is, in our visual-cognitive apparatus decoded again, resulting in the color we perceive, perceived that is, as an intensive quality, implying that (cognitive) decoding takes place via the Implicate Order(-part of the thing).
Also the  holistic constitution  of all substances (in the metaphysical sense) belongs to the province of the Implicate Order :  All the material parts and constituent particles of a given substance, as seen in the Explicate Order(-part of that substance), are non-locally connected to each other via the Implicate Order(-part of that same substance). But because the Implicate Order is not an extensum it cannot be a continuum. However, by connecting parts and constituent particles non-locally to each other, it nevertheless makes the substance into a true  continuum.  That is to say,  seen from the Explicate Order, but also taking into account the Implicate Order, a substance is a true (homogeneous or heterogeneous) continuum.
This (more or less new) "outlook", in addition to Extensionality (previous document), also applies to all the other subjects to be treated, such as Motion, Time, Atoms, Molecules, and Crystals.
In addition to all this, I would like to remind the reader, that the previous document, the present document, and the documents to come, concluding this Sixth Part of Website, are thoroughly Aristotelian as to the metaphysical context in which the inorganic world (and, of course, with it the organic world) is being expounded. What is new (as compared with the original Aristotelian metaphysics), is the embedding of this metaphysics in our theory of the  Implicate / Explicate Orders, which theory is supposed to make additional sense of the Aristotelian metaphysics.
Central in our overall metaphysical exposition are  natures. These natures are  beings, be it substances, accidents of substance, or immaterial forms. The most important natures are those that exist as substances. In the scheme of  "categories" or predicaments (substance, quantity, quality, relation, place, etc.) we have the group of the most general types of beings that can be inferred from sensory experience. This group forms a 'system' of so-called  "pros hen  equivocals", where "equivocals" are real beings, classified in the "categories" and being as to their nature such that they are instances of Being, all referring to a single primary instance of Being, which is substance. So while accidents are secondary instances of Being, a substance is the primary instance of Being. The secondary instances have Being only insofar as they refer, as to what they are, to the primary instance.
About natures, substances, and accidents, we spoke already extensively in  First Part of Website ('Back to Homepage' link), but without yet having developed our theory of the  Implicate / Explicate Order. We returned to it in  Fifth Part of Website :  Theory of natures, part I-V.
Further in that same (Fifth Part) Part of Website, we expounded a logic (i.e. a doctrine of logic, a study of the logical instruments to know objectively existing things) that is especially ordered to Aristotelian metaphysics, here meaning that this is a logic that is subsequent to metaphysics, i.e. dependent on the basic features of things as they are in themselves. The logical entities studied here are, despite having them called "instruments", no instrumental signs, i.e. no mental 'images' of things, but purely intentional signs of which the intelligible content exclusively lies in the things intended, not in the signs themselves. Only in this way  objective knowledge is guaranteed. This logic, " Intentional Logic", is expounded in Fifth Part of Website under the heading  Logic, formal elements of cognition, parts I-VII.

Connection with extensionality.

In the previous document we discussed the fundamental properties of spatial, i.e. extensional, things, and the preconditions that must be satisfied by the "extensional" as  ens  (a being). In a world, composed of extensional things (extensa) we easily recognize, as possibilities  arising from extensionality as such, some typical relationships. Typical that is, because in a purely mental world they would make no sense unless by remote analogy. In a spatial world namely, i.e. in our world, two bodies A and B can touch each other, and then they are close to each other, AB. They can touch a third body on both ends, ACB, and then they are at a certain distance from each other. This contact may change, and if this change is continuous we have motion. Proximity and distance and motion :  Here we have the relationships, the  possibility  of which, as necessarily resulting from the nature of extensionality, is intuitively known by us. The study of all these relationships, typical of the spatial world, as to their very basics, is the philosophy of Place and Space.

In modern philosophies much is said about  space, and little, or in fact nothing at all, about  place.  Aristotle and St Thomas speak a lot about place and little about space. At first sight the difference does not seem to be so important. Nevertheless the difference exists, as will become clear in due course. And it can become very important. To see this, it is now sufficient to note the following :  If, let us say, "place" is, in these matters, primary, and "space" secondary [meaning "derived"], then we, in our philosophical analysis intending to delve into the deepest grounds, cannot take "space" as primarily given and then from it synthesize the spatial world. If we do this nevertheless, then the danger of ending up in error is undoubtedly very big. And history confirms this. We will see that in these matters "place" is primary indeed. Where we should not forget that preceding this whole complex of spatial relationships is the  ens extensum.  This is the primarily given, subjectively and objectively. After our expositions the difference between "space" and "place" will be clear. We do not start with definitions, we will  find  them.

We have said that the possibility of these relationships, of proximity, distance, and motion, results from the nature of extensionality, as properties in the strictest sense of this word, of the spatial things, and that this is  intuitively  given. This, however, is not the case with  all  laws, governing these matters. Among them there are some which, as ordinary physical laws, are known to us not intuitively as to be necessary in themselves, but only known from experience. Therefore we must note a pecularity :  [more or less precisely] that,  what we find in problems of pure geometry, namely that they can be solved by purely-logical deduction from earlier known propositions (theorems), and finally from first data that can be read by intellective insight directly from basic experience (axioms),

HOENEN REMARKS :  We here assume the classical view of mathematical knowledge (in whatever way it should be worked out further). According to our opinion the results of the investigations of the 20th century concerning the foundation of mathematical knowledge do not spoil this classical view. [...]. For our discussion it is sufficient to hold that Geometry is an  a priori  science, not derived from experiments. On the other hand, Mechanics partly is such an experimental science. Where it is not, will be clear to us later.
[As to the 'post-classical view', I presume that HOENEN here thinks of certain results concerning the cognitive foundation of mathematics that seem to legitimate a degree of arbitrariness of axioms in some parts of mathematics. Such arbitrary axioms are then not primary insights.]

we also encounter, but only partially so, in the science of place and motion (mechanics). This deductive part of mechanics is sometimes called phoronomy or kinetics, and this science can be constructed from an insight that is similar to geometric insight. But another part of mechanics, dynamics, especially that (part) which works out the cause of motion has no part in this privilege. It does have it, of course, as to the general principles of causality -- here we have to do not with a mathematical, but with metaphysical insight -- but not as to (all) parts of the specification of the principles. These parts have to be found experimentally. Poincaré says :  " Les Anglais enseignent la méchanique comme une science expérimentale. Sur le continent, on l'expose toujours plus ou moins comme une science déductive et  a priori. Ce sont les Anglais qui on raison." Of course the English are not right. Or better, they would not have been right if they handle things such as Poincaré attributes to them. The "plus ou moins" of the continental scholars, which undoubtedly is also present in the English, better indicates the mixed nature of mechanics. And of course a 'too much of this or a too much of that' will be present in many authors. In addition to the difficulties that always accompany the detection and indication (not the actual knowledge) of the first principles -- analysis in the sense of Aristotle's "Analytica" -- it occurs in the theory of place and motion that experimental laws, that are "evident" to us, or that are teached us from childhood, are taken by us as a-priori-truths.
In what follows we can present only the results of our own [HOENENS's] reflection concerning these problems, because these rather deviate from that what is assumed by many, even coming from divergent schools of thought, and also [deviate] from what may be read in works of scholastics of the later centuries. The more surprising it was when we discovered that the results of our reflection, albeit not in all of its parts, but yet in their essentials, were to be found in Aristotle and St Thomas. More clearly so in St Thomas and in many medievals than in Aristotle.

(See also  Fourth Part of Website, part XXIX Sequel 5 ).
First of all we note :  The concept of  "place where something is"  originates as a result of observation of motion [change, replacement]. In a barrel in which first there was wine, the latter is replaced by air, by water, by sand. Who first was in Athens, subsequently was in Rome, then in London, then in New York. There is an "environment" where the one body replaces another, a body that was first in the one and then in the other "environment". That environment is the place of the movable. If this "to be at a place", and this "change of place" is to be something real, then (in addition to the moved) that  environment  must be a real thing (too). It must moreover be something  different  from the moved [i.e. different from that what is moved from one place to another]. So we now have already two results :  The place must be a  physical reality, and must be something different from the moved [from the placed].
But this determination is still not sufficiently precise. In Rome, in Athens, many are with me. It is a common[ly possessed] place, not the place that exclusively pertains to me. If  I  want to determine such a place, I must take the physical reality  immediately  surrounding me, and this even not in its entire depth or thickness, but in that with which it immediately touches me, i.e. in its surface directed toward me and touching me. The "first surface of the surrounding physical reality", -- this then being the precise determination of "place of a body". In this we should not forget that this immediate environment (these immediate surroundings) should not be thought of as to be apart from the other bodies. The environment is thought of as to be connected with these other bodies, and eventually with those of the whole Universe.
Yet, we still have not reached our goal. The determination [of what place is] also applies to a barrel with respect to its content, but the barrel and its content may be moved, while the concept of  "place" demands immobility. The "placed" may be moved, i.e. placed somewhere else, but the place itself remains. The difficulty of this demand made a great impression in the Middle Ages :  A body, finding itself in running water, without being dragged along with the current, does not have an immediate environment which is at rest, and [this body] would be either itself not at rest, which is against the assumption, or not be at some definite place, i.e. not be somewhere. St Thomas had found an elegant solution :  The  form  of the surrounding liquid remains, while it itself, the matter, moves. And that form has a fixed position in the Universe. The immobility of  "place" must in these cases be taken not as  material  but as  formal.

Definition.
And so Aristotle arrived at his definition. The (proper) place of a given body is the real, first (immediate), immobile, surrounding surface. A body is in motion when it changes place (so defined). One must admit that Aristotle has, with acuteness of mind, reduced the concept of place, as it is represented in our natural consciousness, to its very elements. Is this analysis and its result still useful to science, including modern science?
First a word about the last element [of the definition], the immobility of place. According to a certain principle of relativity (relativity taken in a certain sense, which we will analyze later) on must assume the follwong :  If A moves with respect to B, one may as well say that B moves with respect to A. We can think of sitting in a railway car, running along the track, then we may as well say (and one even has the sensory impression) that the track and the whole environment moves in the opposite direction with respect to us. What should we say about this? For the time being merely this :  We leave Rome in northern direction, we thus move with respect to the city, to Italy, and to the whole Earth. Purely phoronomically, purely mathematically, we describe the same fact when we say that the city, the country, and the whole Earth move with respect to us in the opposite direction. Whether it physically be the same is, of course, not immediately clear, and at first sight even improbable. We will investigate this problem later on. For the time being this may be the answer :  It is always easier ("plus commode" after Poincaré) to say :  We move with respect to the Earth and not the other way around. It is easier, not only in daily life, but also in science. We return to it later. Let us now study the other results of Aristotle's analysis.

Critical investigation.
The first, in fact triple, element, that Aristotle found in his analysis is this :  "place"  is something  real, which is  physically-extended, and which is something  different  from the placed. That these three conditions are essential will be immediately clear. When we say that Socrates is in Athens, or is leaving Athens, and Athens would not be something real, i.e. would be nothing at all, then what we had said would be bare nonsense. The place is something real. And that it is something physical does not need any clarification. Thirdly, this real is something other than the placed or the placeable. In a somewhat banal joke we may answer the question "where is Socrates?" with "in his skin". The popular humour contained in this is precisely humour because it is immediately clear -- and with this we are in the territory of philosophy -- that the place where the man is, is not something of his own body, but something different.

So these three conclusions surely are necessary. May the reader think of them to be só evident that he is surprised that we have even insisted upon them, then the better prepared he /she will be to accept the conclusions that Aristotle has drawn from them, and which might force him/her to correct ideas entertained until now.  " To be somewhere", accordingly, is a  relative to be. If it is to be true for a given body, then yet another body has to be present as well, which is its place, which is the "somewhere", where it is. If  "to be at a place" is relative, then change of place, i.e. motion, also is essentially relative. Being moved, accordingly, is essentially being moved with respect to another real body, to another physical extensum. So let us, for now, suppose that only one body exists, then this body could not be "somewhere", here or there, because an essential element for something to be "somewhere" is lacking, namely the real other. So this body would be  nowhere. Yet it would still exist. We now let go this fiction of the one single body and take with Aristotle the physical universe, outside of which there being no other physical reality, otherwise it would not be the universe. And now also for the universe the above applies :  It is not somewhere, not here or there, it is nowhere. But of course it exists. Further :  If that one body or the universe is not here or there, then it also cannot  now  be here and  then  be there, in other words, it cannot be moved, because also motion is essentially relative with respect to another physical thing, but in our case there is no such other thing. One should be careful :  In the present case motion is not merely impossible because a moving  force  is apparently absent. Even if there were such a force it would not be able to move the one body or the universe as a whole, because the latter cannot  be  moved, for to be moved makes, in the present case, no sense at all. It is as absurd as a square circle or the surface of a line. So if there are philosophers setting up an argument departing from the thesis :  "there is only one single body and this is being moved", then we should not be surprised that they arrive at results that are either just as absurd or at least without value. How it is possible that this absurd assumption has nevertheless sometimes been made, we shall see later.
From this first condition it is now certain that "to place" (i.e. positioning, putting) and "moving" (shifting of place) are essentially relative in the sense that both notions presuppose another, really existing, physical extensum, with respect to it they can only be realized.

The second element found by Aristotle in his analysis consists of the fact that that other physical reality (i.e. object) constituting the place, i.e. that real environment, must also be the  immediate  neighborhood of that what is placed, as soon as we speak about the  own proper, not about the commonly possessed place. And the most immediate accordingly was, as we saw, the inner surface of that neighborhood, touching the placed. How seriously Aristotle took this demand of immediate contact is evident from a conclusion, following from it and which he fully accepts :  " if outside a given body there is another one, surrounding the first, then it is at a place, if not then not ", and so he arrives at the above mentioned conclusion about the universe as a whole, as a special case of this general conclusion. This demand of immediate contact with the surroundings, as a condition for a body  " to be somewhere", is for many perhaps too strong. Especially when one is aware of a consequence of this thesis, namely this :  Two bodies having no physical contact with each other and neither with other bodies, would be without mutual local relationship, and would not be at a (certain) distance from each other. This latter is so important a thesis that it is worth the trouble to carefully enquire into the principle from which it results. Because nobody has more clearly posited this principle than has St Thomas, we, a little later, will fully investigate it under the title :  " Theory of localization of St Thomas Aquinas ".

Remark.
Still one more element of Aristotle's definition [of place] must, for a while, have our attention, namely the fact that for him "place" of a body is a surface. Generally one should expect rather a thing with three dimensions, as also has the placed itself. Wouldn't this have to be corrected by, for instance, saying that that part of  space  enclosed by this surrounding surface is the place of the body? Aristotle does not accept this. The space is something entirely imaginary, having no reality in Nature. So it cannot figure as "place", because "place" must be a real extensum. Aristotle no doubt is right. Nevertheless we can, following this remark, accept a correction or at least a completion of Aristotle's theory taken from a datum of modern physics, namely the aether of Lorentz.

The aether of Lorentz as medium of localization.

Already for a long time, and with changing views, physics had, in addition to and situated between "ponderable" matter, assumed another, also extended, reality, an "imponderable" matter, called aether. Usually it was described as being a liquid, a very rarefied one indeed, having the mobility of liquids. Also a kind of atomistic structure was attributed to it. The fates of such an aether we do not follow here -- later we will have the opportunity to do so. In the present context it is only important to learn to know it as it received its perfect description by Lorentz. In the beginning of his theory of electrons it reads :  "One of the most important of our fundamental assumptions must be that the ether not only occupies all space between molecules, atoms, or electrons, but that it pervades all these particles. We shall add the hypothesis that, though the particles may move,  the ether always remains at rest". So for Lorentz the aether is not a mobile liquid anymore, but rather a solid, or better an ultra-solid matter, in the sense that its parts mutually take up an inextricable position. Therefore the aether is not an aggregate of atoms, but a continuum. However, it is not solid in the sense that it would be an obstacle to movement of particles being embedded within it. On the contrary :  to this, i.e. to "ponderable" matter, it is perfectly penetrable. Had Aristotle -- and many with him -- considered all bodies to be mutually impenetrable, because daily experience seems to teach us this clearly, sophisticated modern art of experimentation has brought to light facts for whose explanation Lorentz had to assume a matter penetrable to ordinary matter, and with the mentioned properties. And that a penetrable extensum is indeed possible we have seen earlier (previous document). This aether [or "ether" as one may write it] is a really subsisting spatial entity, because it  interacts  with ordinary, "ponderable" matter. This interaction may, for these ordinary bodies, cause movement with respect to the aether and with respect to one another. However, this interaction does not cause movements of parts of the aether itself. Yet the eather is intrinsically, qualitatively changeable, because it is the carrier (substrate) of electric and magnetic (and also of gravitational) fields which are invoved in such changes.
Now see :  the parts of this aether of Lorentz perfectly do satisfy all conditions posited by Aristotle for the [kind of] reality that has to take up the function of  "place". The [surrounding (and penetrating) ]  parts [regions] of the aether do form a  real, spatial thing, and, with respect to any given (physical) body, they are something  else, i.e. something other than the bodies that find their "place" in them. And all this we've learned to know as absolutely necessary conditions to be satisfied by something in order for it to be a "place". These parts or regions of the aether are more "immediate" with respect to the "placed" bodies than is the immediate environment, which Aristotle had to be contented with. Here, not a mere external contact, but what we may call an internal contact between the placed body and the region concerned of the surrounding [and penetrating] aether :  coinciding of every part with every part, of every point with every point. And so we've also got rid of the objection, encountered while inspecting the old theory, that the "placed" had three dimensions while the "place" had only two. The further condition, that of immobility, is perfectly satisfied by the parts of the aether of Lorentz. Finally, the  mediate  contact between bodies embedded in the aether is guaranteed by the continuous nature of the aether [and in this way guaranteeing the possibility of bodies being at a distance from each other]. Indeed, the parts of the aether [i.e. the parts of the aether that on occasion take part in constituting the place of some given body] do indeed completely realize the Aristotelian notion of "place". The aether of Lorentz is the perfect medium of localization, despite the fact that it wasn't because of that that it was originally conceived.
However, there are still problems to be solved. First we have the wide-spread opinion that the aether-theory of Lorentz was a mere nine day's wonder in the history of physics. Einsteins theory of relativity is said to have finished it off.  This is more or less generally expressed by physicists. Evidently this demands further inquiry, the more so because it is connected with the second demand of Aristotle, the immobility of "place". After all, according to this immobility one can, at least physically, not hold any longer that  "A moves with respect to  B " is equivalent to  " B moves with respect to A". And then a second problem is to be solved :  The aether's continuity does actually guarantee, it is true, the mediate contact between all "ponderable" bodies, and thus the reality of their distances, but has the philosophical problem left unsolved whether this mediate contact is actually necessary as it was held by Aristotle and St Thomas. Let this second problem -- as the most important of the two -- now be first investigated (as it is done in the main Section  Localization theory of St Thomas Aquinas  further below).

In  Fourth Part of Website ,  part XXIX Sequel-5, we already discussed the aether of Lorentz as possibly constituting a universal medium of localization (of objects). There we saw that it cannot be the aether as a concrete object that can serve as such a medium, because, as a concrete object -- a substance with accidents, especially those that  per accidens  inhere in the substance -- it can and does change locally. Because of its importance we here repeat the Section  "Ontological Analysis of the Ether as universal Medium of Localization" in part XXIX Sequel-5 of  Fourth Part of Website :

Ontological analysis of the Ether as universal Medium of Localization.
Every real full-fledged being can be considered to consist of Substance and Accident, or, in other words, of properties (accidents) plus that (substance) of which they are properties. If it were not so constituted, it would be difficult to consider it as real. The ether, if it is to be a medium of localization, must be a real being (as established earlier). So it must ontologically be constituted by substance and accident. But as such the ether can change, and would not be an appropriate localization-medium. A way out of this dilemma could be the following :  Precisely the 'naked' substance, i.e. its substance without accidents, i.e. that which remains the same during (accidental) change, is the medium of localization. This medium would not be real if it did not have accidents (properties). But it does have accidents. It is only that these accidents do not participate in the ether being a universal medium of localization. Only its substantial aspect does. That this, not seen as a being, but as an aspect of a being, is real enough can be illustrated by the substantial aspect of any ordinary physical body that is an intrinsic being. Let's take snowflakes. They all differ in appearance, even when grown in uniform conditions. Especially they differ in morphology. But their chemical composition is the same, and also their crystallographic symmetry (expressed by their Space Group) is the same. As was established in First Part of Website (Crystals and Metaphysics) the  Essence  of a single crystal is its Chemical Composition plus its Space Group (symmetry). And this Essence represents the substance and was called the genotypical domain of the given being, which here is a crystal. From this Essence flows part of the crystal's phenotypical domain, consisting of intrinsic properties, like the crystal's point symmetry, its electrical and other physical properties, and also its chemical properties. In addition to these properties the crystal also displays extrinsic features (constituting the other part of its phenotypical domain) such as resulting from irregular growth, caused by fortuitous irregularities of the growing environment.
This description should, however, be a little amended :  In fact the mentioned crystal's chemical composition plus its space group symmetry -- because as such this is already a full-fledged physical structure -- already belongs to the crystal's phenotypical domain, the domain of the observable consequences of the crystal's Essence (its genotypical domain), and the latter can be identified with the particular relevant crystallization law (as dynamical law of a dynamical system, which is the growing crystal in its nutrient environment). It is this crystallization law that, as Essence of this particular crystal, cannot change, because in that case we would obtain a specifically different crystal  (Realize that the Essence, insofar as it is this particular Essence, cannot change. Only the crystal can change, and when this change is a substantial change -- and thus not an accidental change -- we have to do with a specifically new Essence of the crystal. This could happen, for instance, when a given crystal metamorphoses its intrinsic structure as a result of change of certain external conditions like temperature and pressure.). In the same way the direct (phenotypical) consequences of the Essence of the crystal, for example the space group symmetry and point group symmetry as intrinsic properties (and only as intrinsic properties) remain the same, while other features like the particular shape and morphology that the crystal has actually taken up, changes, when say, ice crystals are concerned, from snowflake to snowflake. Of course the intrinsic properties could change, but only as properties, not as intrinsic properties of the initially given crystal, and then they become intrinsic properties with respect to another species of crystal, for instance, with respect to chemical composition, when Oxygen is replaced by Sulfur (at low temperatures), or, when its space group symmetry turns into another space group symmetry (  These are substantial changes, about which we spoke just above). But in a snowfall this does not happen. And it is this case we consider illustrative for something remaining the same within something that changes constantly. And the  ether  is now considered to be something that remains the same -- and can as such serve as a medium of localization -- within an ontologically broader entity that can and does change all the time. This ontologically broader entity, which as such must be a full-fledged being, is composed of (a particular) substance plus (its) accidents, intrinsic or extrinsic, and could, or even should be -- because a universal medium of localization not only demands just extension, but extension in and around all objects that obtain place -- some physical field. Maybe several physical fields are involved, that, however, ultimately unite to be one field after all, and the ether would then be that aspect of this field that remains the same. And this aspect will then consist of the (unified) field's Essence plus that what necessarily flows from it, i.e. that which is immediately implied by it, which is the set of intrinsic properties. What we observe however, is neither this Essence, nor the intrinsic properties insofar as they are intrinsic properties, but only actually existing features. The Essence plus intrinsic features does not change as long as the substance does not change, i.e. is not annihilated. This means that our unchangeable entity, demanded by the contact theory, is a theoretical construct, not a physical entity. And this goes someway to explain why the Michelson-Morley experiment failed to demonstrate it :  Motion can only be measured when it is motion of  a  body,  i.e. of an ontologically complete entity, with respect to another such body.
This interpretation, here presented, of the nature of the localization medium differs from that of HOENEN, because he maintains that this medium is a full-fledged substance, i.e. a complete being, its substance plus its accidents. We say that the medium of localization is only an ontological part of such a complete being. It is the theoretical construct (or, equivalently, the ideal entity) as outlined just above. And its reality wholly derives from the reality of the complete being of which it is an ontological part.
If our medium of localization by means of which a body obtains its place, were uniform and homogeneous, then every place would be the same, which means that motion with respect to this medium would be impossible. But our medium is not necessarily homogeneous. We have said that this medium of localization (insofar as it is a universal medium of localization), is the constant structure that is immediately implied by the Essence or intrinsic nature of the complete entity of which the medium is just an ontological part. And if we now assume that this constant and permanent structure is non-periodic (otherwise many places separated by certain distances are exactly the same with respect to local structure as well as to orientation), then our medium is a true universal medium of localization. It is an abstract heterogeneous continuum.
If there really exists such a universal medium of localization, then the place of a body is a unique place when it is related to this medium. But can a place really be unique, i.e. can we demonstrate this without assuming this medium ? Yes we can. We will derive it from absolute simultaneity.

There, i.e. in part XXIX Sequel-5 of  Fourth Part of Website, we, following Van MELSEN, 1955, and also HOENEN, 1947, demonstrated that the Theory of Relativity presupposes the possibility of absolute simultaneity. And we concluded :

There is no possibility to measure this simultaneity. And this is a true result of the theory of relativity. Therefore the concept of simultaneity does not make sense in natural science, but it does make sense as one of its presuppositions, and as such it is a truly philosophical concept. So in our metaphysical (and thus philosophical) analysis of reality, which is a consideration of the way and status of Being and beings, we can accept the existence of absolute simultaneity.

And such a simultaneity implies the existence of absolute place (absolute position), because of the following reason :
If at location  x₁  an event  g₁  takes place, then a simultaneous event  g₂  cannot take place at location  x₁ .  It can, however, in principle, take place at any other location (i.e. at any location which is not  x₁ ). And this shows that the location  x₁  is unique with respect to a given event. In the same way we can couple a different event to another point, say  x₂ ,  and so on with respect to every point whatsoever. All this means that  place  is something absolute. And this means that we have found with all this a second indication of the truth of the contact theory  ( The first indication was conceptual in nature, it drew from the concept of ens extensum). And after having established objective place, absolute motion follows as a consequence, because motion is continuous change of place.
As we have said, absolute simultaneity cannot be objectively measured, and so, consequently absolute place and absolute motion cannot be so measured, And that's why the outcome of the famous Michelson-Morley experiment was negative.

Let us explain the above argument further :
It says "If at a location  x1  . . .". Such a location (place) is as such not yet taken as being uniquely determined, because that has to be demonstrated. It is identified as that place where event  g1  takes place. And it is clear that at the same time -- taken as local time -- the reverse of this event, the event  g2,  cannot take place at  x1.  Now, we might consider the possibility that at a place  y1  (being at a certain distance from  x1 )  the same event  g1  takes place, rendering the place  x1  not-unique. However, we might safely assume that the overall collocation of things and events in the world does not admit a precise repetition of a precisely defined event, because conditions, including relevant conditions, are nowhere the same in this collocation. So we may say that place  x1  is uniquely defined by event  g1 .  Of course the event  g1  will once cease to be at place  x1  and replaced by another event. But because every precisely defined event will only take place once in all history of the Universe, we may say that place  x1  is uniquely characterized by the fact that once  event  g1  has taken place in it.
I am aware that this 'argument' is probably not complete, or even in all respects correct. It is just a preliminary establishment of the possibility of absolute place (location) and absolute motion, without using the notion of "universal medium of localization" such as the aether of Lorentz.

Introduction

We have arrived here in a more or less peculiar situation. The theory which we are about to present, and of which the principle is given in so clear a way by St Thomas, much clearer than it is done by Aristotle, and whose consequences were also defended by various medievals, has, in later times passed into oblivion completely. In pondering for years about these problems we thought to have found this principle, and saw in it the solution of many difficulties, not only in natural philosophy. And only then we found it already being expressed with the greatest possible degree of clarity and definitenes in St Thomas. Still greater was our surprise when read it also in ... Einstein, albeit it hard to have it compatible with his own theory [of relativity].

Let us start to ask a question that one is not used to ask. And the fact that one doesn't ask it is, we believe, the cause of the troubles in this problem. Here then the question :  Suppose two physical bodies lying next to each other, either touching each other or at a certain distance from each other, for instance, touching a third body lying in between. Now what is primary here, is it the situation (close to one another or at a distance) or is it the contact (with each other, or with a third). In other words, do the bodies first have their  position, and then, as a result of that and of their sizes, contact, or do they first have  contact  with one another and then [as a result]  position? By the terms "first" and "then" are not meant, of course, a succession in time (both are surely simultaneous), but an "order according to nature" or according to origin. So we can ask the question also in this way :  Do they touch one another (or a third), because they have those mutual positions, or do they have those positions because they touch one another (or a third)? Said differently, does touching result from position, or does position result from touching?
St Thomas answers this question very decidedly and clearly :  As a result of contact bodies have their position, and not vice versa.
Most philosophers -- and perhaps even most people -- do not seem to even think about this possibility -- for St Thomas the exclusive one. They do not ask the question, and take, of course not explicitly, but yet actually, as datum :  First position, then (dependent on other positions) contact or distance. Also the later scholastics do this, but they dig deeper than the other "modern" philosophers, who apparently do not detect the problem, and look for a theory legislating their assumption. Their theories share the following :  Bodies owe their position to an "intrinsic modality", calling it the intrinsic "ubi" [= where?]. This modality first has an -- though completely unknown to us -- effect  in  the body itself and from it then result the mutual positions :  either contact or distance. This is a necessary hypothesis as soon as one considers "contact" not as primary [meaning that contact results from position. We here consider things statically, not dynamically, and so it should be :  Accordingly, we speak about something having a position, and not how this position has been secured by a change from another position. This is because motion is, with respect to place or position a derived phenomenon :  motion is change of place or position.]. In the working-out of the "ubi-hypothesis" there were many differences. We can reduce them to two classes. The first category assumes that from the "ubi" of one body already does result a position, a "place" in space. Notice, this "space" is also by these philosophers not taken as a reality. From this naturally follows that  one single  body (so also the universe as a whole), in virtue of the fact that it may have now this and then that "ubi", is able to move. From this would follow the possibility and actuality of place and movement that are not relative, not with respect to another reality. The impossibility of this we have already seen. We do not have to look further into this theory. Therefore, a second category of  "ubi-theories" came up. These demand the existence of at least two bodies, each one with its own "ubi", and from these two in this way intrinsically modified bodies "contact" respectively "distance" would result. From a change of at least one of these "ubies" motion would follow. All local movement then must suppose an intrinsic modal change in those bodies. The fact that St Thomas (as indeed Aristotle too) in his theory denies that internal change in, i.e. in the case of, locomotion, is clear [because contact, being primary, presupposes at least two bodies, both 'undergoing' contact].
So it is now our task to test both remaining theories as to the rational content of their elements. We will call the theory of Aquinas, holding "contact" as primary, the  Contact Theory, while the other theory, taking the position resulting from the "ubi" as primary, will be called the  Position Theory.

The first-known and first-understood in these matters is always :  the  ens extensum (the spatially extended being), the spatial thing. We may ask :  Can we make intelligible, departing from the nature of this extensum, the relations of "place" and "motion" in the Contact Theory, which says :  first the body-to-be-placed touches the other body functioning as "place", and only then it is "there" (i.e. only then it has position), and not vice versa?
That this is so, is, indeed, and surely immediately, intuitively, clear. We experience in ourselves the  intellective insight  [of the fact] that from the nature of the spatial results,  that is, necessarily  results :  the capacity to touch one another [i.e. to be in immediate physical contact with one another]. And just as immediately then follows :  these two bodies are in each other's immediate vicinity. We continue. See next figure.

We consider a system consisting of a rectangular parallelepipedum (C) and two cubes (A and B) each one of them with a face touching one of two opposite faces of the parallelepipedum (C), the possibility of which [i.e of such a configuration] is certain. We experience again an intellective insight in our mind :  From this double contact a  distance  results, having the length of a face of the pallelepipedum between the touching faces of the two cubes.
Now a different case. See next figure.

The two cubes may be in direct contact with the body C as in the above figure. The length of the line on the body C be  a.
Again it is immediately clear that the opposing faces (or their centers) of A and B are at a distance from each other equal to  a.  This again results from the contacts.
Now let the contact of A with C change continuously (this is a new capacity which we have experienced intellectively). We may call this a "flowing contact" (shifting A along C, while continually touching C), now taking the place of the static picture we had before. Again, we immediately see that now results :  Movement of A with respect to C, and also (because there is mediate flowing contact) with respect to B  [ A is in flowing contact with B, through C ].  The distance from A to B becomes larger or smaller. Purely phoronomically or mathematically we may, as was already said above, describe the movement also as follows :  The system BC moves with respect to A. Whether this is so also physically, will later be investigated.
Let us again consider the situation in which these three bodies are at rest, while supposing there does not exist any other physical body. Then, [precisely] between A and B an empty space "exists". The assumption that only these three bodies exist apparently is possible, and from this the great difference with the theory of Descartes [ French philosopher, 1596-1650] is clear. According to this theory, A and B should touch each other, because  nothing  is between them, or, if they are at a distance from each other then automatically there must necessarily exist a body between them [i.e. a fourth body must be assumed]. We, accordingly, say :  "there exists" an empty space of a determined size [volume] between A and B.  This "existence" should not be taken litterally, because that space is not an  ens, not a being (after all, only the three bodies exist and their mutual contacts), and the "nothing" cannot exist. It is an elliptic expression by which we want to express nothing else than this factual situation :  Between A and B a fourth body, if we had it to our disposal, may be placed with a maximum length of  a.  When it is larger, then it doesn't fit between A and B. When it is smaller, then yet another body can be placed between them. All this again is immediately clear. Also  outside  this three-body-universe an empty space "exists", stretching out indefinitely. This again is an elliptic expression to describe this actual possibility :  The number of bodies may be increased [and so increasing the volume of the universe] and brought into physical contact with the universe already existing (i.e. with the initial 3-body universe), and this  ad infinitum [and this we can express by saying that there is, in addition to the three bodies, infinitely extending space].  Indeed, all fundamental relationships found in matters of  "place", "space", and "motion", are in the Contact Theory perfectly intelligible [when departing] from the first datum :  the spatial thing, the ens extensum, and the possibility of them [i.e. of place, space, and motion] necessarily follows from that first datum. They are completely intelligible, apart from one difficulty, it is true, about which we will speak in due course.

Application to the aether.
After all, we want succinctly show that all this remains perfectly intelligible when we accept the addition to Aristotle's theory that was found above in the aether of Lorentz. In this theory of the aether a body obtains its position or place in virtue of  "intrinsic" contact, as described above, with a part [region] of the aether. And this is immediately clear :  If two bodies coincide with two contiguous parts [here 'parts' together forming one continuous whole] of the aether, then they are in each other's vicinity. If they coincide with parts of the aether far apart, then a distance between the two bodies immediately results, a distance being measured by the length of the aether-part between then. ["parts of the aether far apart" should here not be understood as "being at a (larger) distance from each other", but as conceptually-taken parts of the aether continuously connected by other parts of the aether so conceived.]  Flowing intrinsic contact with the parts of the aether again is the source of motion of the bodies among themselves. And, might we, possibly, not actually [be able to] observe movement with respect to the aether [as the Michelson-Morley experiment has demonstrated], we can observe the resulting motion of the bodies with respect to each other. So also to the aether of Lorentz as medium of localization the Contact Theory remains perfectly transparent. If indeed the aether of Lorentz does exist (we will return to that later), it may, or, perhaps, has to, be viewed so, i.e. viewed as a [universal] medium of localization.

We have called the contact theory of St Thomas perfectly transparent, apart from one difficulty. Here that difficulty. If contact between real bodies is the only source of local relationships, then two bodies, neither immediately, nor mediately (through another body or a series of these) touching each other, will  not  stand in any local relationship. They will neither be in one another's vicinity, nor be at a distance from each other. One may say :  "the two bodies touch nothing", but this means only :  "they do not touch something". And from these two negations no positive relation can result. If they are not at a distance from each other, then they can also not be at different [varying, changing] distances from each other, meaning that also motion of these two bodies with respect to each other is impossible, it doesn't even make  sense.  And all this seems to directly contradict that what our common-sense view or vision [aanschouwing] of things is supposed to teach us so clearly. In the [astronomical] space of our imagination we do so clearly and so easily  place  two completely separated bodies, being at a certain distance from each other, a distance that, moreover, may vary, resulting in us to see just as clear the mutual mobility of these bodies.

Analysis of our common-sense view or vision.
We must, however, watch carefully the actual data contained in this common-sense vision, and not be led astray in interpreting them. What, then, is the content of this common-sense vision? We imagine a space, and at different parts of this space we place [put down] the two bodies and detect their distance. And if we let change the latter, then we detect their motion with respect to each other, and with respect to ourself which is the center of this space. And then our  intellect  says :  "that space is nothing", and then we interpret our common-sense vision as follows :  Also in empty space two bodies can, without any real contact, have distance and may move. And this interpretation is  false, for in our common-sense vision that space is a real thing indeed, a real extensum (having even a dark color) and we place the two bodies into different parts of that reality. The space of our common-sense vision is a perfect representation of the aether of Lorentz. [Indeed, here it is not about imagining a mathematically empty space, but about a physically empty space. And then we do imagine a true ens extensum.]. And if the intellect reads in it that distances and movements are necessarily possible, then we have nothing other than a confirmation of what we already saw :  In the Contact Theory, also in the case that the aether is a universal medium of contact, all elements are completely intelligible.
So in the just described imagination we do not have the case the possibility of which would constitute an objection against the Contact Theory, namely the case of two bodies without any contact, be it direct or indirect [because 'empty space' is conceived in our imagination as a real ens extensum, i.e. not as a "nothing"]. Isn't then our imagination able to construct such a case (objecting against the Contact Theory)? No it can't.  We are not able to imagine the "nothing" (i.e. truly empty space). Of course, our imagination might [in such a case] perhaps not work, and then we do not have this view or vision [having no view or vision at all], but that doesn't mean that we see the "nothing". There can be no vision of the "nothing". So when we imagine a body, we place it into space by means of internal contact, a space that is in our representation real, and we place it at a certain distance from ourself, and then place a second body in the same way, and then all things in this complex are connected with each other through that milieu, imagined by us as real [We immerse bodies into a real sea of space, i.e. into a real ens extensum, and this ens perfectly complies with the nature of the aether of Lorentz.]. The alleged difficulty confirms the intelligibility of the Contact Theory, and only constitutes an objection in the case of incorrect interpretation of the data of our common-sense vision. So we have to accept as a conclusion [flowing] from the Contact Theory :  If  there would be two bodies -- or two worlds for that matter -- standing in no contact whatsoever with one another, then they would not be in each other's vicinity, neither be at a distance from each other. They would be without local relation at all, they would, so to say, not exist  for one another.
Can such a case appear? St Thomas discusses the hypothesis of two completely separated worlds, and rejects it. Not because the conclusion would not follow from the assumption, but because of the latter itself. The assumption, namely, that there could be two creatures without any mutual relationship, without any order, is absurd to him, because of the necessary order [that must exist] in the work of the single Creator. Bonaventura [also 13th century] accepts the assumption, at least as a thought-experiment, as one would say today. And then his conclusion is :  no vicinity and no distance [For these we need contact, contact that is, of bodies, directly or indirectly, i.e. contact of given bodies with each other or through one or more other bodies]. And with him many medievals say so.

Might one consider this question whether two separate worlds are possible to be unimportant, another question is of the greatest importance to natural philosophy :  If the Contact Theory is the right theory, then a theory as that of Democritus, which constructs the world from a swarm, floating about in empty space, of particles, particles totally separated from each other, not connected by any real medium,  is absurd [and, of course, only when "empty space" is equated with "nothing", and not with merely some other type of ens in addition to that of the particles]. Between such particles no distance is possible, and so also no change of distance, no movement. Maybe Democritus has seen this, and so his thesis that "also the not-being exists" may find an explanation. Then this "salto mortale in negation" is in the end a shift of this absurdity, or, if one wants, an emphasis of it. [If we replace in this context "not-being" by "empty space", and then say, with Democritus, that "empty space exists", then we have affirmed the existence of something like the aether of Lorentz.]. All this under the assumption that only the Contact Theory is intelligible, while the Position Theory is not. But the latter still has to be investigated.

So the Contact Theory says this :  In such relationships [distance, movement] contact is primary. And the possibility of contact is intuitively immediately evident as following from the datum of two real extensa [two spatial things]. Thus,  first  contact,  then  position, and that  with  immediate contact [we get] nearness,  through  mediate contact [we get] distance.
The other theory, which we had called the Position Theory, says :  first  position,  then,  either contact by nearness [i.e. physical contact as a result of (a special) position,  or distance [i.e. no physical contact as a result of (some other) position].
The absolute Position Theory, attributing to already one single body a place in empty space, and in it holding movement to be possible (absolute place and absolute motion), we already have found to be false.
Remains the relative Position Theory, which does attribute to every physical body a position, i.e. an internal[ly determined], though totally unknown to us, determination, accident, or modality, but letting result from it a relation only to other real bodies (having their own internal[ly determined] position). This relation then may be either contact (nearness) or determined distance.  If  the possibility of distance in the absolute vacuum does exist, i.e. without mediate contact through other real extensa existing, then one surely will need the Position Theory for an explanation. But does such a possibility really exist? One a-priori-construction of this possibility was already analyzed above, where it was read off from the datum of our common-sense vision, which apparently confirms it. But analysis of this datum has teached us that this was only seemingly so. What we read off from this datum is merely the complete intelligibility of what the Contact Theory teaches us. From contact with a real milieu distance results. This be enough.
One has tried out another construction. Suppose that two bodies touch a third one at both its sides (see Figure above ).  They then will be at a determined distance from each other, measured by the size of the third body. Now suppose that this third body is annihilated while nothing else happens. Then there is, so one argues, no reason to assume that that determined distance would vanish. This argument seems to appeal to many. Nevertheless it breaks down upon further analysis. First we note that in the argument in the beginning the contact theory is presupposed :  distance has resulted  from  the double contact. Then one lets annihilate the third body (to which we make no objection), and then one assumes that nothing else happens. But against this we do have a certain and decisive objection :  If the third body is annihilated, then necessarily two other things disappear, namely the two contacts. Then precisely that disappears, which, according to the supposition from which the construction departed, made distance possible, i.e. that from which it had resulted. And so the distance disappears with it. Of course not in such a way that now the two bodies have become near to each other -- that was supposed to be the case by Descartes -- but in such a way that no local relation exists anymore.
We may construct an analogous case :  When signaling apparatus and receiving set of a telegraph are connected with each other by a firm wire, the signal will reach the receiver. Now we suppose that the wire has been cut without anything else happening. And now the same kind of reasoning would result in the conclusion saying :  now there is still no reason that the signal would fail to reach the receiver. Why is here the absurdity immediately evident, while in the first case for many (apparently) not? The cause is clear :  In the first case the reasoning is accompanied by this view :  We see the three bodies in the configuration described. It is easy to let the third disappear, and see, - the two other remain at the same distance from each other. But the reason is clear. They are still connected by space, which, in our common-sense vision is something real [a true ens extensum]. But then we do not have the situation that was argued [i.e. complete vacuum between the remaining two bodies]. So also this construction of the a-priori-possibility of a distance so conceived lacks any value.
Is, then, this possibility [of distance across a vacuum] derivable from the intelligibility of the elements themselves out of which the Position Theory is built, as this was the case in the Contact Theory? We have [in the position theory] the internally determined positions of the bodies at our disposal [i.e. according to the theory they are given], the nature of which [positions], however, is  totally  obscure to us. And when two bodies, each one with its own position, are given, then, from these data contact or distance is supposed to result, as in the Contact Theory distance did result from a double contact with a medium. The necessity of this latter resulting was intuitively clear to us, as was also intuitively clear the capacity of the extensa for [having] contacts from which distance results. [So in the Contact Theory the primary datum, contact, is itself intuively clear]. But in the Position Theory we precisely find the opposite :  The nature of the internal[ly determined] positions escapes any understanding whatsoever [i.e. here the theory's primary datum is in itself unintelligible], and just as total is our lack of insight in distance resulting from these presupposed positions. [We might come up by saying that  position-as-internally-determined  is as such caused by some definite movement, or, said differently, the present position of a body is the result of previous movement, or, yet in other words, the particular internal or intrinsic positioning of the body has resulted from a particular movement. Apart from the problematic nature of these statements implied by the Position Theory, movement is presupposed with respect to position. But movement itself is no more than change of position. So movement presupposes position. And thus, position presupposes position. So in itself "position", the primary datum of the Position Theory, remains unintelligible.]  In our investigation of this theory -- the position theory -- we haven't made any progress at all down the path to intelligibility. Things have become even more obscure than they were at the outset, when we thought to understand things at least a little.
But we did not yet find the Position Theory to be impossible, we did not encounter internal contradiction, or contradiction with other certain data. And yet this is contained in what we've already found and described so far.

Recall what we have seen :  from the notion of extensum necessarily follows the capacity to have contact between two extensa. Of this we have intellective insight. Is this merely a conviction, following from, certainly in this respect rich, experience? No it is not.

Examples.
To see this more clearly, three examples may be instructive. First, one regarding properties of which we do not have lesser practical conviction, but a conviction resting on pure experience only. After that, two examples of certainty based on intellective insight.

• We suppose we have two little bars having the same shape and size, one of lead, one of steel. The lead bar we can easily bend, and after cessation of the force it retains its bent shape. The steel bar, for a much lesser degree of bending, demands a far greater effort, and after it it regains its original shape. Of these facts, and of the general law of which we saw a special case unfolding from such a law, we will surely be convinced. Why? Because prolonged experience has teached us it. But also after such prolonged experience we do not have, from ascertaining the facts,  insight  of the necessary following up of the properties from the nature of the two materials.
• Let's consider an [arithmetic] addition. We have seven things and add five, and we are forgotten that the result of this operation is twelve. Well, we can arrive at the knowledge of this result and to the insight of its necessity by  executing  this operation. We have the seven, and add one by one, the others until the supply of them is exhausted :  eight, nine, ten, eleven, up to twelve. This procedure looks purely experimental, it is almost an mechanical process. But to what we want to call attention is this :  Our operation is accompanied with  intellective insight  into the  necessity  of the result, insight originating from our understanding of the object of the operation, and of the operation itself, namely multitudes, numbers, and their addition. It is not a  pure  experience [i.e. it is not experience alone]. So we should take notice of especially that insight.
• A third example. We consider a triangle. Through one of its angles [and remaining within the triangle] we draw a straight line. We do not have to suppose a mathematical triangle, but merely a certain triangle from our sensible experience. The sides of the triangle are thus not lines, but stripes having a certain width, they are not perfectly straight, but only so for mere vision, as is also the line having been drawn through the vertex (angular point, which itself is no mathematical point). In our vision this line intersects the opposite side of the triangle. Also this is no  pure  datum of experience, it is accompanied by the insight that this intersection necessarily follows from the nature of extensionality and of this particular figure realized in it.
  Note :  With the origin of this insight the theory of knowledge, not natural philosophy, should deal. In considering the foundations of Geometry another problem asks for a solution, how, namely, from the above sketched  inaccurate  data of sensible experience, does originate the  accurate  intellective knowledge. And also another one :  how generic generality originates. (end of note)
  Again, to this intellective insight we must devote our attention.

Remarks.
We've said that this theory of St Thomas was rather generally abandoned, and apparently not known anymore. It took us [HOENEN] years of struggling before we reached this view, and only then we encountered it in St Thomas described as the most evident case in the world. This is one of the many reasons why we admire the genious of the angelic Doctor, who, apparently has this insight without any trouble, without even mentioning the alternative. From this it is also understandable why he, with so much assurance and so much open-mindedness is used to say that local motion does not bring with it any internal change in that which is being moved, a thesis that was unjustifiably abandoned also by so many of its followers [We here should think of what precisely motion of a body really is. And we do so by considering first of all regular motion, i.e. rectilinear motion with constant speed. What we here see is a continuous change of position of the body in motion. And St Thomas thinks it to be impossible that this change of position reflects some internal, qualitative, change in the body in motion. Later we will learn that motion is the extensional effect of a quality having come to inhere in the body. But this quality, the "impetus", is not connected with the position, or successive positions, of the body in motion :  As the body, being in regular motion, continually changes position, its "impetus" remains the same as to its intensity. Only an increase of impetus, caused by a force (newly) applied to the (moving) body, results in an increase of speed (acceleration) of that body. After cessation of this force the increased speed remains the same as well as the increased intensity of the impetus of the body.]  Nevertheless this insight is apparently present in all [thinkers, i.e. not only in St Thomas], and the difficulty merely consists in making explicit and formulating the principle. For everybody, including those who deem distance to be possible in the absolute vacuum, or even [adhere to the possibility of] absolute place and motion, do place their bodies in the space of imagination, which is, in that vision, a reality, and there place and distance do indeed originate according to the Contact Theory. Only later they forget the fact that this space has no reality in Nature, and that the Contact Theory cannot be applied to the vacuum [between physical bodies]. For we've already said, "touching nothing" is "not touching" and cannot lead to real distance and to its consequences. [Also to them who realized the imaginary nature of space, we may say that initially in their imagination they (unconsciously) did apply the Contact Theory, because in their imagination space was real. But when they later realized that their "space" was only of an imaginary nature, they forgot, in admitting the non-reality of space, that now the Contact Theory is not working anymore. That is to say, they should realize that distance in a vacuum between bodies has been thrown away together with space. Distance should have become unintelligible for them. They have never realized that they, in their imagination, conceived distance according to precisely the Contact Theory. Therefore they kept on believing that distance still exists in a vacuum between bodies. But instead, they should replace the imagined space by something like the aether of Lorentz, and so restoring the possibilty of overall contact.]
So the difficulty apparently lies only in making explicit and formulating the principle. But isn't that strange? Not so strange as it might look at first sight. At least we have some more examples of the same phenomenon.
Above we gave the example of the line running through the vertex of a triangle and necessarily intersecting the opposite side. This (at least being a similar insight) is one of the "order-axiomata" (axioms of order) of Geometry. Well, these order-axiomata have been used all the time and never formulated or as such indicated before the year 1882. In that year they were "discovered" by  M. Pasch. This case is even stronger when one realizes that already for half a century investigations were going on as regards the axioms of Geometry, investigations being done as a result of non-Euclidean geometries, investigations in which it was paramount to list  all  axioms. Why weren't these axioms not formulated? Well, because they were so "evident". So the case of the Contact Theory does not stand alone. We take it to have found a similar example in the two insights that, according to us, precede the insight of  7 + 5 = 12.
While the Contact-Theory was essentially abandoned by modern scholastics, and much more so in others, the more surprisingly we read it in ... Einstein. Here are his words, which we cannot interpret to represent something other than the formulation of the Contact Theory, although he lacks the clarity of the angelic Doctor :

" Ihm (dem Raume) geht die Bildung der objectiven Körperwelt voran. Ich kann Körper durch sinnliche Merkmale wiedererkennen, ohne sie bereits räumlich zu erfassen. Ist in solchem Sinne der Körperbegriff gebildet, so zwingt uns die sinnliche Erfahrung dazu, Lagen-Beziehungen zwischen den Körpern festzustellen d.h. Relationen der gegenseitigen Berührung. Was wir als räumliche Beziehungen zwischen Körpern deuten is nichts anderes. Also :  ohne Körperbegriff kein Begriff räumlicher Relationen zwischen Körpern und ohne den Begriff der räumlichen Relationen kein Raumbegriff."
( A. EINSTEIN, in the periodical Forum Philosophicum (having enjoyed, according to HOENEN, only a brief existence)
I (1930),  p.173. The italics are HOENEN's )

As to its importance, we [JB] translate this passage into English :

" The formation of the objective world of bodies precedes space. I can recognize bodies with the help of sensible features [i.e. features that can be detected by the senses], without them conceiving already spatially. Has then, in that sense, the concept of body been formed, then sense experience forces us to determine relations of position between the bodies, i.e. Relations of mutual contact. Indeed, what we take to be spatial relations between bodies is nothing else. Accordingly :  without a conception of "body" there is no conception of spatial relations between bodies, and without conception of spatial relations there is no concept of space."

Here, much is said beautifully, namely (1) that the concept of  "space" is secondary with respect to the concept of  "body" or "extensum" [i.e. the concept of (physical) "body", with all its features, including its extensionality, is prior to the concept of  "space" (in which the bodies are supposed to reside) ],  and (2) that local relations result from contact of these bodies, and (3) that from these relationships the concept of space is constructed. The positivistic slant that will be recognized by specialists in these lines [i.e. the emphasis that all we have about reality are merely logical constructions of our investigating minds] is not taken by us to be our responsibility, and the special reason [to express ourself in this way] is clear enough from our expositions. Whether this view -- as to contact being primary with respect to distance -- of  Einstein (in the periodical mentioned) is compatible with his own theory of relativity is a different question.

We already spoke about the concepts of absolute and relative motion in the original sense of the words. In this sense all motion turned out to be necessarily relative, i.e. motion with respect to another real extensum. Absolute movement, i.e. not with respect to some other reality, or with respect to the "nothing", doesn't make sense. Accordingly, "to be somewhere" presupposes another reality, different from that which "is somewhere", namely the "place" where the placed is, and the "nothing" turned out to be not a "place" where a body might be. In this sense the thesis :  "all motion [which is a continuous change of place] is necessarily relative" is evident. Notice :  This thesis not merely means :  "in order to  observe  motion, another reality is needed". No :  the other reality is needed for the very  being  of motion.

But, we already pointed to it, the term "relative motion" is also used in a different sense, namely in this one :  If A is moved with respect to B, then, as one says, one may as well say that B moves with respect to A. One claims that also this follows from the concept of motion, like the first mentioned sort of relativity did so follow, and one adds that this expresses itself in observation, in virtue of the fact that all physical laws valid in A, experimentally without having changed do apply in B.  A rather vague criterion, about which we will say some words later. Now we merely see what follows from the concepts, as they are intelligible to us.
So this, one also calls the relativity of motion [A with respect to B, and B with respect to A].  A better formulation would read :  the relative [aspect] in [the phenomenon of] motion is mutual, there is an equal or reciprocal, or, as it is expressed in modern logic, a symmetrical relation. Then motion would not be merely relative, but in addition also symmetric-relative. Such a symmetrical relation is, for instance, the relation of equality :  If A is equal to B, then B is also equal to A.  If, then, motion is symmetric-relative, then the last demand of Aristotle :  "place in the strict sense is immobile, only the placed may move" must be dropped. On the other hand, the first two demands, namely the place is something different, a different real extensum [different from the placed], and :  place is in contact with the placed, are preserved.

But  is  it true? We already said :  phoronomically or kinetically seen, it is clear. One may equivalently describe what happens (the pure passive) with the words :  A moves with respect to B, and B moves with respect to A. Whereby one should notice that there is no complete symmetry :  the motions in both descriptions have opposite directions [Of course opposite equal motions are symmetrical with respect to one another. Here, however, "symmetry" is supposed to mean "equivalence"].  If  A  is a body, and B the aether, then the descriptions read :  "A successively passes through the parts B1, B2, B3, etc. of the aether"  and  "those parts successively pass through A",  in which there is complete symmetry [body A passes through B1, and at the same time B1 passes through A. Then A passes through B2, and at the same time B2 passes through A, etc.]. Tacitly it is assumed (and this may become paramount) that in both cases all parts of the aether with respect to one another are not subjected to shifts. So there is only a difference of description, not in the real aspect of the motion. At least if we stick to the purely mathematical [= phoronomical] aspect of it.
But motion is also something physical. Added is an actual "being", an actual "flowing contact", which turns out to demand an actual cause [this is the physical aspect], which soon will bring with it an intensive factor, the speed. This is already not purely mathematical anymore. Possibly then the symmetry of the relation ceases to exist.

Example.
See here an analogous case, not a proof, but an illustration. We have two lines equal to each other, A and B. This relation is purely symmetrical. Later we find out that they have become unequal :  A is longer than B. In this relation there is, it is true, no symmetry, but there nevertheless does exist a reverse relation. For we may formulate the new datum also in this way :  B is shorter than A.  But how should we express the "becoming", of which we find the result?  A has become (from equal) longer than B?  B has become (from equal) shorter than A?  According to the purely mathematical proportional aspect both formulas are equivalent. But they surely are not so as soon as we want to express the physical event. The "becoming" expressed in both formulas evidently is not the same. The first formula is true if, for instance, a segment is added onto A, or, also, if it is stretched. The second formula is true if a segment is taken away from B, or when it has shrinked. And there are indefinitely many other possibilities. Notwithstanding the equivalence in the mathematical proportion, the physical "becoming" is in these cases different [to physically paste something onto A, is different from physically take away something from B ]. This could also be the case in the phenomenon of motion.

" Motion"  physically [taken] is not symmetric-relative.
At first sight, however, not so [i.e. there doesn't seem to be a difference between the phoronomical and physical aspect of motion], as follows from our description above [about a body A moving with respect to the aether B ]. On first inspection, the symmetry of "placement" by contact [i.e. from contact, position follows] appears equally well existing in the case of motion. And purely phoronomically it is so. But not so anymore as soon as one inspects things as to their physical aspect. Suppose, to pinpoint thought, that a body A is submerged into an aether. When the body  starts  to move, of course with respect to the aether (If one wishes, one may assume other bodies to be present in the aether in order to be able to observe in it a coordinate system), then all  new  distances of A (or points in A) to all points in that aether  immediately  result. This is not something following from observation,  no,  of this we have intellective and immediate insight.

Here  motion with respect to the aether  is supposed to be possible. If the aether were homogeneous, and indeed homogeneous into the extreme, meaning that it doesn't even have boundaries (even when being of finite size), then it is hard, if not impossible, to imagine the movement of some given physical body with respect to such an aether. But the aether is not believed to be homogeneous. It is believed to be a heterogeneous continuum as a result of locally varying qualitative determinations of it, such as electric, magnetic, electro-magnetic, and gravitational fields. These fields being carried by the aether. But these varying qualitative determinations are caused by ponderable bodies (electric or magnetic bodies, light-emitting bodies, heavy bodies), which are themselves in motion. So if we take the motion of some given body to be with respect to the heterogeneity of the aether, then its motion is in fact with respect to other ponderable bodies. So as things stand, a body cannot move with respect to the aether, even when the latter is a heterogeneous continuum.
A way out of this dilemma may be the following :  Aether and ponderable bodies penetrate each other. We draw an imaginary line through the aether (without knowing where in the aether this line is). On this line we draw an imaginary point. Now we can draw another point on this line at a certain distance from the first point. Indeed, this distance is possible because these two points make contact with a third entity lying between them (being now a genuine part of the aether, measured along the imaginary line). Through each of these points we draw a line perpendicular to the first line, and now it is possible to draw a line precisely at equal distance from the first line. It is clear that in this way we can draw an imaginary coordinate system in the aether. And now, having this coordinate system, and using it as a reference-system, we can, finally, legitimately speak about the movement of some given physical body with respect to the aether.

It is good that the reader is convinced by the fact that the distances from a body that starts to move with respect to the aether [distances] to all points of the aether do change  immediately,  and that this is a direct intellective insight. Yet another reflection may further be instructive :  As a result of the change of distance, also the  action,  that may emanate from the body  A  [submerged in the aether, and starting to move] and enforced upon remote points [of the aether], will change. Does this changed action, in particular its effect, establish itself also immediately in all these remote points? By merely reasoning we cannot come to an answer, and one already sees (in one's mind) the difference with the change of mere distance [immediate change of distance being intellectively clear, immediate change of effect of action of A upon all remote points not being intellectively clear]. Further, experience has teached us that this is not the case. All action to propagate itself and then to have effect needs time. So let us be clear about three things :  (1) the  insight  that distance immediately results, (2) the fact that we do not have that insight as regards action (its effect), and (3) that experience teaches us the opposite [no immediate effects of the action]. Well, precisely because these distances, at the beginning of, and further during, the movement of the body A, change immediately, we can, purely phoronomically, describe the movement of A with respect to the aether also in this way :  That aether as a whole moves with respect to A.

To this "principle of the immediate resulting of distances" we will return later (and did already so in Fourth Part of Website, part XXIX Sequel-5) when discussing the possibility of absolute simultaneity. Here one should notice that in this we have a development and confirmation of the Contact Theory of St Thomas.

But beginning of motion (as we assumed for body A) demands, if things are fully considered as to their physical aspect, an active cause whatever this may be (later we will see that also the continuation of a regular rectilinear motion demands such a cause, albeit not a "force" in the technical mechanical sense), and this influence (of that cause) is governed by the law of all material action, namely that it doesn't propagate instantaneously. This influence will  immediately  have to manifest itself there where the place-relation has its origin, namely at the sites of contact between the body A and parts of the aether occupied by A, upon all contact-sites or upon some of them. If the motion (the "becoming") is attributed to A [and then the aether not being supposed to move],  A  moving, of course with respect to the aether, then it will proceed, as one usually describes it, with a small deformation of A, if A is small  [When A is small, the influence soon reaches from one side of the body to the other, and then only for a short while there is some deformation at the site where the influence began],  and none if A is seized upon in all its points at the same time.
Does one, on the other hand, want to ascribe the motion actually to the aether with respect to the body A, then the influence must first seize upon the contact-sites of the aether and then move it.

If the aether moves at all, just like that, then it may do it with respect to another body than A, say to the body B. The motion of the aether may then be zero with respect to A. Accordingly, to be sure that the aether moves with respect to A, it cannot be aether-movement just like that. The body A must play a role. And so in the aether, commencing motion with respect to A, not just any points of the aether can be seized upon, but only its points of contact with A.

The remote parts of the aether will feel this influence [deformation, propagating from the points of contact with A that were seized upon in order to move the aether] only after a certain time has elapsed -- perhaps only after an astronomical time :  The aether would be deformed, and we do not have the same course of events as we had in the first case [A moves with respect to the aether].

If the motion is exclusively attributed to the small object (this resides in a much larger object, the aether), then only this smaller object can deform, and this deformation is only very temporal. The aether [in this case] is not deformed, because it does not, ex hypothesi, take part in the motion.
If, on the other hand, the motion is attributed to the aether, then the small object cannot be deformed, but the eather can, and will, because of the large distance to be traveled by the internal contraction-wave propagating from one or more sites of contact of the aether with the small object to the periphery of the aether if there does exist one [it must be presupposed when attributing motion to the aether]. Indeed, as long as the internal contraction-wave has not entirely traversed the body, the latter is deformed. When it has traversed the body, the latter as a whole has moved.

When one wants to assume the same influence on both, body and aether, then one obtains a third case [the second case becomes different from the first case]. So physically "motion" is not symmetrical-relative [at least not without exceptions. Here, the case of the assumed existence of an aether].

Yet another reason for [attributing] asymmetry to motion.
The last consideration leads to yet another reflection, that, independently of the first reflection, leads to the same result. It lays bare a possibility, being entirely neglected in classical mechanics. There one knows Newton's law of action and reaction, which reads :  When a body A applies a force onto a body B, then B applies an equal, but opposite, force onto A.  Force must here be understood in the technical-mechanical sense and is measured by the product of mass (m) and acceleration (a) :  F = ma. This law is not  a priori  evident, it was in classical mechanics considered to be confirmed by very rich and precise observation. But this observation only applies to "ponderable matter". Does it also apply to a body A and the aether in which it is submerged (even apart from measuring this force, in which the "mass" of the aether would, of course, trouble things)? Also here it is  a priori  not evident that this or a like law would apply, and experience certainly doesn't teach us this.
Let us consider the following case. There is an active cause, moving A with respect to the aether, and this cause should seize primarily upon the points of contact. The fact that this cause will  influence  both, A and the aether, will be clear. The influence on A manifests itself as motion (change). And, when only a part of A is seized upon, this influence will propagate as a result of internal forces in A, the one part dragging the other with it. But is the influence in the aether also :  a tendency of  displacement  of the seized-upon parts?  A priori  this is far from evident. Surely, the mechanistic philosophy of nature did not know of another type of change, but this philosophy is in its very fundamentals false. So the possibility of an additional [type of] influence is not  a priori  excluded. It could consist of a  qualitative  change of condition in the aether. If there indeed is this possibility, then the  motion  can only be attributed to the body A, and not to the aether. The motion is then not symmetric-relative. One should keep in mind, that we here still investigate only whether from the very  concept  of motion follows that it is symmetric-relative as many assert it to be. From our proof, which presupposes the  possibility  of qualitative change in the aether, already sufficiently follows, that from the concept "motion", provided that it is considered completely physically, does not follow that it is [always] symmetric-relative. This consideration may have been neglected in classical mechanics, but does not take away anything from its merits.

Realization of the conditions of asymmetry.
Should we not say more, shouldn't we say that the influence of causes, which for bodies are causes of motion, but in the aether indeed bring with them qualitative changes only? Above we spoke about "an eather" in general, without specification, as about a thing of which abstractly we considered its possibility. Now let us take the aether as the one that is, as a product of the historical development of physics, specified by Lorentz, the "aether of Lorentz". Haven't we there before us indeed an extensum in which the abstract possibility is realized? Let us one more time read the description of the properties of that aether by Lorentz (1909) himself :

"One of the most important of our fundamental assumptions must be that the ether not only occupies all space between molecules, atoms or electrons, but that it pervades all these particles. We shall add the hypothesis that, though the particles may move, the ether always remains at rest."

So we learn to know this aether as a real extensum, penetrable to the particles of  "ponderable" matter, resulting in the fact that the bodies can move [through the aether] without any friction, and where also the parts of the aether remain at rest with respect to one another. Is therefore the aether unchangeable? On the contrary, it is the substrate of intrinsic,  qualitative  changes, alternating "tensions", that are the elements of  "fields", gravitational, and electromagnetic fields (the periodic alternations of the latter form radiation). The specific nature of these qualitative changes is not known to us. But we do know that these two fields differ from each other, and that there is a connection between electric and magnetic alternations (for which mathematical formula are known, the famous equations of Maxwell). Also our not-specific knowledge of these electric and magnetic qualities is acutely described by Lorentz in the same article :

"On account of the difficulties into which they [the theories of a mechanical aether] lead us, there has of late years been a tendency to avoid them [i.e. all those mechanical explanations] altogether and to establish a theory on a few assumptions of a more general nature.
The first of these is, that in an electric field there is a certain state of things which gives rise to a force acting on an electrified body which may therefore be symbolically represented by the force acting on such a body per unit of charge. This is what we call the  electric force,  the symbol of a state in the medium about whose nature we shall not venture any further statement.
The second assumption relates to a magnetic field. Without thinking of those hidden  rotations  of which I have just spoken [these belonged to the mechanical aether], we can define this by the so-called  magnetic force,  i.e. the force acting on a pole of unit strength."

First Lorentz has described the bankruptcy of the mechanical aether whose changes consist in shifts of its parts with respect to one another [as were they to comply with F = ma], in order to now introduce his immobile aether with purely qualitative, electric and magnetic, changes. That "state of things", those "assumptions of a more general nature", are a typical description of a qualitative condition [state of things] (we will return to it later and then will see that this  qualitative  condition can be measured as to its  intensity  and expressed by numbers) which [condition] is known to us only generically, not in its specific nature, and [known] as to some effects (attraction and repulsion of electrified bodies, the connection between electric and magnetic alternations). Analogously, the same aether is substrate of gravitational fields. This aether of Lorentz, contrived to account for electromagnetic phenomena, is indeed the aether whose possibility we had derived in our above consideration of an absolute medium of localization, an aether, whose parts remain at rest with respect to one another [ex hypothesi :  the aether can deform qualitatively] because they cannot be seized upon by any shifting force, and, finally, an aether, in which only qualitative changes are possible, so that  motion  of bodies with respect to this aether physically must be attributed to these bodies, and [this motion] therefore being not symmetric-relative. This aether of Lorentz also satisfies the last condition demanded by Aristotle for something to be a "place".
But, one might reply, the aether of Lorentz has, after a short existence, been eliminated by the special theory of relativity of Einstein [The latter theory was published in 1905, largely motivated by the negative outcome of the Michelson-Morley experiment in 1887, while Lorentz's exposition of the aether (referred to above] was published in 1909.], and thus, so one might say, we cannot re-introduce it as a realization of an Aristotelian notion. It doesn't seem to be real. Later on we will investigate this. First we have to describe a new, third, meaning of the pair of concepts "absolute and relative motion", being introduced by that same theory of relativity, and generally used today, [but] not in order to clarify the concepts.

The special theory of relativity (still considering regular rectilinear motion only, while the general theory of relativity (1916) also accounts for accelerated motion) posed as a general principle that the motions of (ponderable) bodies with respect to one another are relative in the second sense, that is, symmetric-relative, and asserted that the laws of physics, being observed in one given system [of physical configuration] also must be observed as unchanged in a system that moves with respect to the first with constant speed. This was found to be the case here and there [i.e. confirmed in experience, that certain laws remain the same in such systems]. In other cases, for instance as to the principle of Doppler [holding in all such systems], [such an invariance was] even derived from the theory. By Einstein it was taken  hypothetically  to be generally valid. So this theory of relativity poses as a principle the symmetric relativity of motion of  ponderable  bodies. This symmetric-relativity cannot, however, exist in [all of] reality (notice, that perhaps many laws may show this invariance mentioned above) if the aether of Lorentz exists. Suppose, namely, that motion is observed of A with repect to B, both ponderable bodies. If A is at rest with respect to the aether, then necessarily B moves with respect to the aether. If we now -- in this same situation -- attribute the motion to A, and the resting state to B, then we must attribute this motion also to the aether [because A is at rest with respect to the aether] (in a  description  this is permitted). If we -- still in the same situation -- attribute the motion to B, then with A the aether is at rest. So in reality [if the aether of Lorentz exists) the relation is not symmetric. [The aether is not (supposed to be) ponderable, while A and B are. So  A + aether  is not an object that is equivalent to the object B, and precisely this causes the asymmetry]. Thence the statement of Einstein, and of many with him (straight away we will hear some assertions), after the [publication and success of the] special theory of relativity :  the aether of Lorentz does not exist.
Einstein thought he would need the principle saying that the motions of directly observable, i.e. ponderable bodies, are symmetric-relative. This is the principle of relativity, his hypothetical point of departure. If an aether exists, this symmetry is impossible in Nature. It is granted that in many cases the  actually existing  invariance of natural laws can be explained without this symmetry actually existing (i.e. when an aether is assumed), but, as Einstein thought, not in all cases [i.e. if an aether is assumed, then not all cases of invariance (symmetry) can be explained, and, consequently, if the aether is abandoned, all cases of invariance can be explained.]. And that this symmetry does exist in all cases without exception precisely was his  hypothesis. Therefore the aether had to disappear [because that precisely is the one case for which it is not valid].
From this follows the third meaning of the pair of concepts "absolute and relative motion", generally in usage today :  Who accepts the aether of Lorentz and thus the motion of bodies being primary with respect to the aether, assumes [the possibility and existence of] absolute motion. Who denies existence of the aether and thus motion with respect to the aether, only accepts relative motion. The difference with the original meaning of the pair of conceps [i.e. motion being independently all by itself --- motion always being with respect to something else (without necessarily assuming symmetry) ]  is clear [for motion with respect to the aether is, in spite of being not symmetric-relative, relative nevertheless], but is not always realized.

The aether of Lorentz.

The special theory of relativity.

So after the special theory of relatively had been established, the aether of Lorentz was rejected by Einstein, and this rejection has, among physicists, though not unanimously, become so frequent that one would be considered hopelessly old-fashioned when one would doubt whether this rejection is legitimate. Nevertheless we will venture to critisize it.
One rejected the aether as a result of the fact [found out in the Michelson-Morley experiment] that one could not observe a motion of the Earth with respect to such an aether (in many cases it turned out that, according to the theory of Lorentz, one indeed could not do this even with this aether's presence, but not in all cases may one assert this without a new hypothesis), and [the aether was rejected] because Einstein had hypothetically generalized this case [movement of the Earth with respect to the aether] :  Never will it be possible to measure such a motion [In this, one should realize that although it is legitimate within natural science to equate "something being not measurable (i.e. observable) in principle"  with  "something cannot exist", this equation cannot be absolutely valid :  the fact that something cannot, even in principle, be observed, does not necessarily entail that it therefore does not or cannot exist.].
Nevertheless there may be another reason to demand the existence of the aether, and that reason nowhere has been refuted. This fact encourages us to take up the critique of the special theory of relativity in denying the aether.

The aether as real field.
So his decision as to the non-existence of the aether surely was somewhat too hasty. The same conclusion (of our's) follows from yet another consideration. The aether of Lorentz was [meant to be] the substrate of light rays, i.e. of electromagnetic waves, and, although one had not succeeded to measure, from light phenomena, the speed (of our Earth) through the aether (that was Einstein's point of departure), these waves could still not be eliminated as a result. Was this perhaps connected with Einstein's attempt, dating from the first years of the theory of relativity, to introduce, instead of waves, photons, representing a sort of particles? The theory of photons undoubtedly was successful, but yet not in the sense that they would lack any wave-nature. So between ponderable bodies there exist periodic alternations of electromagnetic qualities (we'll speak about these later), but these are with metaphysical necessity the changing qualities of a spatial substance, being again the aether of Lorentz. [The point is that qualitative changes are empirically given in the form of propagating periodic changes in intensity of electric and magnetic magnitudes. So in the light phenomena the existence of qualities is established. But then a substrate carrying these qualities must also exist. This means that these qualities must be the further determinations of some substance (in the metaphysical sense), and this substance must be spatial, because of the observed propagation, and is, of course, the aether of Lorentz. And it is, perhaps, the 'naked' substrate of these changing qualities that represents the universal localization-medium.].
After all, even when one had succeeded to reduce light-rays to swarms of flying particles, then there would still be, in the milieu between ponderable bodies,  static  electric fields and  constant  magnetic fields, things that are physically active, and wich are qualities once again, real intensive states in [and of ] an extensive substance, i.e. in [and of ] an aether. And to any alternative explanation, or even any explanation whatsoever, of electromagnetic properties, nothing has been contributed even by the later general theory of relativity. See here an utterance of Einstein which one almost would be inclined to attribute to a kind of gallows humour. He says in the  above mentioned  article:

"Sie [i.e. the theoretic construction of the general theory of relativity] gibt also gerade von jenen Phänomenen nich in logisch befriedigender Weise Rechenschaft, denen die ganze Relativitätstheorie ihren Ursprung verdankt."

Translation :

" It [i.e. the theoretic construction of the general theory of relativity] does not account, in a logically satisfying way, for precisely those phenomena [the electromagnetic phenomena] from which the whole theory of relativity departed."
[i.e. the special theory of relativity, antedating the general, was concerned with electromagnetic phenomena, and precisely these phenomena were not fully accounted for even in the general theory of relativity.]

So we must conclude again, but this time as a result of the properties of light and of the existence of static fields outside the ponderable matter :  The aether of Lorentz was too quickly discarded by the special theory of relativity.
And see! By the general theory of relativity it was brought back again. Some investigators, among them Einstein himself, again speak about the aether, but say that it is not a "substantial aether", and other researchers therefore reject the  word  aether. Nevertheless all assume a reality which in fact possesses the localizing properties of the aether of Lorentz, here studied.
So Einstein introduced in the general theory of relativity (GTR) a gravitational field, and even managed to detect properties of it, among them this one that the gravitational force propagates with the speed of light. This gravitational field has physical qualities, there are tensions in it, and generally, [these tensions] at different points [are] different and changeable. There are gravitational potentials. As a result of these qualities the gravitational field acts on masses, exerts a real physical influence. Then this gravitational field is, accordingly, a really existing thing. A "nothing", or a mere thing-of-reason, doesn't exert any physical effect. This real thing, existing between ponderable bodies, has extensionality. It fills space. So the field itself is an extensional substance (i.e. a thing that  is  in the strong sense of this word), or it is a qualitative structure on a substance (then it is an accident [in the metaphysical sense], a thing that  is  in a degraded sense, namely that is on something else which then is the substance. And this is the right view philosophically [of what the gravitational field, or any other field, is] ).  [The gravitational field is an accident of the aether of Lorentz, which itself is then the substance carrying this accident]. So the general theory of relativity (GTR) introduces an extensional substance in addition to the ponderable bodies [For if it introduces an accident, then it should mention also its substance]. Well, this is indeed the aether of Lorentz. Let us [see further below] hear some utterances about this aether, from which it is clear that the gravitational field possesses the properties which we have described, and at the same time [let us hear these utterances] to show the philosophical errors by which one had arrived at the denial of the substantial nature of this aether.

Before continuing HOENEN's discussion (1947) about the nature of the aether extending between and through all ponderable bodies, it is perhaps, instructive to translate a long passage from ZWART, P.J., 1988 :  "Het Wezen van het Zijn" (= the essence of Being) (written in Dutch) [this passage] dealing with Einstein's theory of relativity, i.e. the special (1905) and general theory (1916). But before we do this, we first translate a consideration [also] of ZWART about the nature of the supposed "aether" (ether) [So what follows are two quotes from ZWART. Comments and additions of mine are placed between square brackets] :

The Ether (ZWART, 1988, p.115-116)

Today [1988] one has generally agreed that the description of light [and all electromagnetic radiation] as a wave-phenomenon is the most adequate. So light can best be seen as a vibration propagating with high speed, thus a so-called running vibration. The big question then is  what  exactly vibrates. The usual answer that this are electric and magnetic fields is often considered as unsatisfactory, because such a field is nothing real, no reality. After all, the field is purely potential. If somewhere there is, for example, an electric field, then this means nothing more than that  if  there is at that locality an electrically charged particle the latter would feel a certain force [Of course, it should be realized that a merely potential entity cannot act on another entity. It must be a real entity.]. But a photon [a light-particle with frequency] surely is something real,  after all, it acts, it can result in a change of the environment, it has energy and is observable. In the previous [i.e. the 19th] century it was usually assumed that light was a vibration of one or another material medium, a very rarefied matter, called the ether. This assumption seemed to lose its foundation when Michelson and Morley could experimentally demonstrate that the speed of light [in vacuo, i.e. when not passing through a ponderable medium] is constant, not depending on the speed of the emitting nor on that of the receiving body. After all, if there were a resting ether, then moving bodies would have a speed with respect to that ether and thus also with respect to the running vibrations in that ether. The effect of this would be that we would find out that the speed of light with respect of a body would be dependent on the speed of that body, and this turned out not to be the case. This result can only be explained by either assuming that there is no ether, or by supposing that the magnitude of an interval in space or time is also dependent on the speed, namely such that the changes in length and temporal duration precisely compensate for the changes of the speed of light. This indeed takes place in [i.e. is described by] the well-known Lorentz-transformations, also further playing an important role in the theory of relativity.
Nevertheless, from the beginning of the 20th century, the ether-hypothesis was rejected by almost all physicists. There was no way to demonstrate the existence of the ether, and thus one assumed that light propagates without any medium taking part therein. Said differently, one assumed that light [and all other electromagnetic radiation] is not a vibration of the ether, but an electromagnetic vibration. However, above I already had pointed out that this doesn't help us much, because we also don't know what precisely an electromagnetic field in fact is. Apart from that, also here the opposing views are gradually coming closer again, after the point where the indications gain more and more strength that matter also is, in essence, a kind of vibration. Surely, a mass-particle is a kind of turbulence in a quantum- or vacuum-field, and a photon a vibration in an electromagnetic field, but the nature of both fields is unknown. It is in principle very well possible that these fields are identical. When "ether", "quantum-field", and "electromagnetic field" were three different names meaning one an the same thing, a potential being which we also may call "space", this would mean that matter and radiation are essentially identical. Because space as such has no reality, but is only potential, it is further also not possible to speak of the speed of a body with respect to space. Along these lines one would also be able to find a solution (at least formally so) of the riddle of the constant speed of light. [In this first quote from ZWART we cannot assume that he uses terms like "potential being" and the like correctly, i.e. as they should be so used, namely as they are understood in Aristotelian metaphysics.]

The Theory of Relativity (ZWART, 1988, p.132-136)

Validity of the natural laws.
In Chapter 6  I had already indicated that the theory of relativity can be viewed as a consequence of the principle of uniformity, the postulate that says that nature always and everywhere behaves in the same way, namely that always and everywhere the same natural laws reign. Usually one here thinks of universal validity in time and space, but one may of course also think about validity in all possible different systems [physical configurations]. This is in fact what Einstein did when asking whether in coordinate-systems moving with respect to one another the same natural laws hold. We know, for instance, that the universe is expanding and the question is whether we may apply the natural laws valid here on Earth also to a star-nebula moving away from our solar system with high speed.
Einsteins reply was :  Yes, provided that the values of certain magnitudes such as length, time, and speed, are adequately adapted. These adaptations are indicated by certain modifications (transformations) in the relevant formulas. For systems moving uniformly (i.e. with constant speed) with respect to one another these are the Lorentz-transformations, being part of the special theory of relativity (STR). For systems not moving uniformly with respect to one another the transformations follow from the formulas of the general theory of relativity (GTR). Further it is important to note that in the theories of relativity it is only about the laws of mechanics, and that other laws of physics, for example those of thermodynamics, are totally left out of these theories. The STR resulted in the important conclusion that the length of an object (for instance a measuring rod) and the duration of a temporal interval do not have constant values, but being dependent upon the state of motion of a system with respect to the observer. [This connection of how things are with respect to an observing subject may bungle things a bit as to what the objects observed precisely are in themselves independently of these objects being known or observed. That is to say, in natural science the ontological aspect (= what things possibly are in themselves) is very often confused with the epistemological aspect (= whether and how things can be known or observed), that is, results of natural science often only concern the epistemological aspect, but are presented as ontological aspects.]. Also the mass of a physical body is, according to the STR not a constant magnitude, but increases with the speed of that body. From this it follows in turn that mass is in one or another way connected with (kinetic) energy, and vice versa. Initially this was expressed by saying that mass and energy are equivalent, or that mass represents energy, and vice versa. But gradually one began to equate both magnitudes just like that. In the book  The Evolution of Physics,  which Einstein wrote together with Infeld, dating from 1938, this development takes place in three pages :  While on page 256 we can still read " matter represents energy and energy represent matter", on page 259 it is simply "matter is energy and energy has mass".

The general theory of relativity.
The equivalence of matter and energy led Einstein to the idea of a field theory of matter, and that is what the general theory of relativity (GTR) in fact is. In the 19th century a matter-particle was viewed as a mass-point, surrounded by a gravitational field with a rapidly decreasing intensity. This field formed the expression of the fact that a second particle, approaching the first, felt a force of attraction, rapidly increasing as the distance between the two decreased. So this gravitational field represents a certain amount of potential energy. Matter is mass, field is energy, but because mass and energy are equivalent, matter and field must also be equivalent. "Matter is where the concentration of energy is great, field where the concentration of energy is small ... the division into matter and field is ... something artificial and not clearly defined ... We could regard matter as the regions in space where the field is extremely strong" (EINSTEIN and INFELD, 1938, p.256-257). So according to this theory a particle is nothing else than a particular spot (a singularity) in the gravitational field, a view that seems to me not entirely free from circularity, because, on the one hand, the masses determine the structure of the field, but on the other hand the masses being nothing else than particular structures in that field [So mass ==> field, and field ==> mass]. In his book  The meaning of relativity (1953) Einstein reaches the same conclusion via a somewhat different route :  " The special theory of relativity suggests that we might discard the concept of material point and deal only with the field concept .... In general relativity the inertial system is replaced by a field. The space aspect of real things ... is a quality [!] of this field ... one cannot keep side by side the concepts of field and particle as elements of the physical description. The field concept requires freedom from singularities, while the particle concept ... is [means] a singularity in the field. The field concept, however, seems inevitable, since it would be impossible to formulate general relativity without it ... a pure field theory, however, has before it the gigantic task of deriving the atomic character of energy ..." (EINSTEIN, 1953, p.162-165.)
The GTR in fact means a return to the cartesian concept of matter. As we saw in chapter 15, for Descartes the essential feature [earmark] of matter was its extensionality. Later this was replaced by impenetrability, and still later by mass. But today's field theory of matter again shows much similarity with the cartesian view. Einstein himself was well aware of this, as demonstrates the following quote :

"Gemäsz der allgemeinen Relativitätstheorie hat der Raum gegenüber dem "Raum-erfüllenden" keine Sonderexistenz ... Descartes hatte demnach nicht so unrecht, wenn er die Existenz eines leeren Raumes ausschlieszen zu müssen glaubte. Erst die Idee des Feldes als Darsteller des Realen in Verbindung mit dem allgemeinen Relativitätsprinzip zeigt den wahren Kern von Descartes' Idee :  es gibt keinen "feld-leeren" Raum ... Allen Versuchen die allgemeine Relativitätstheorie weiter zu entwickeln gemeinsam ist es, das Physikalisch-Reale als Feld auf zu fassen, wobei dies Feld eine Verallgemeinerung des Gravitationsfeldes ist."
(EINSTEIN, 1916).

Let us translate this quote :

"According to the general theory of relativity, space has no existence apart from "that what fills space" ... Descartes was not so wrong in denying empty space any existence. Only the notion of the field as constituting the real, connected with the general principle of relativity, shows the true nature of Descartes' view :  there is no "field-free" space ... Common to all attempts to further develop the general theory of relativity is to take the physically-real as a field, whereby this field is a generalization of the gravitational field."
(EINSTEIN, 1916).

The universal field.
From the above it will have become clear that the GTR is incompatible with the idea of an independent space and time ( Newton's absolute space and time). There is no empty space. There is only a field, on one occasion called 'gravitational field', on another 'quantum field' or 'vacuum field'. And if we, for convenience, nevertheless continue to speak of "space", we must realize that this [i.e. 'space'] is not a passive framework in which things have a place and through which they move, but a reality, meaning that it acts on things. Einstein has replaced 'actio in distans' [action through distance, action across empty space, unmediated action] by an action of matter on space, plus an action of space on matter. "Space acts on matter, telling it how to move. In turn, matter reacts back on space, telling it how to curve." (MISNER et al., 1973).
From this we see that Einstein tried to reduce all interaction between physical bodies to structuring of space. And this is, accordingly, more or less opposite to the theory expounded in the previous chapter, in which this interaction was reduced to the exchange of bonding-particles. This latter is a genuine physical theory, while the theory of Einstein essentially is geometrical, in which it is only about trajectories followed by moving bodies, without having to use the concept of force. According to me, in the present context the physical interpretation of phenomena should be preferred above the mathematical, because in the first we depart from the real, observed, behavior of systems, while in the second we base ourselves on an idealized conception of the structure of the world, namely a mathematical model. And here we find the cause of the failure of GTR :  It attempts to force recalcitrant reality into a mathematical staitjacket in which it doesn't fit. "General relativity is a splendid piece of mathematics built on quicksand and leading to more and more mathematics about cosmology." (BRILLOUIN, 1970.
On the other hand, Einstein was rather strongly positivistically inclined, and a large part of his views is the direct result of his operational definitions of length, temporal duration, and the like, definitions that should first of all be useful in practice. This type of definitions -- [ contrasting with quid est definitions (definitions expressing what a given thing is in itself)] [Operational definitions result from the desire to strip natural science of metaphysics. A desire long since superseded.] -- may, however, easily result in difficulties. If one, as did Einstein, defines "time" as to be that what is measured by a clock, and one doesn't expound in detail what a clock is, one assuredly gets into trouble. Because then one tacitly assumes that a clock is an instrument to measure time, rendering the definition circular. And a circular definition has no content whatsoever, and from a concept without content one may derive everything, including opposite conclusions. This explains why Einstein arrived at such bizarre notions like curved space and delayed time.
The value of the theory of relativity is, according to me, especially to be found in the connection it establishes between the formerly strongly separated concepts of matter, energy, and light [the latter taken generally as electromagnetic radiation]. Einstein has demonstrated that these realities are closely connected to one another, albeit too far to speak of identity. [I think it is more or less sloppy to speak, in the case of matter, energy, light, simply about "realities" just like that. "Matter" should mean "the existing material bodies", "energy" should mean "a possible quality of material bodies", and "light" (electromagnetic radiation) should also mean a quality, this time a quality, not of material bodies, but of some medium between such bodies.]  A second important step taken by Einstein has been that he proposed the idea that the mentioned realities might be reduced to structures in a field. This, namely, suggests the possibility that these things [matter, energy, light] might also occur in a none-concentrated condition, i.e. not as quantized, but as diffuse, being smeared-out over the whole field. Unfortunately, Einstein did not succeed to work out these ideas in a satisfactory way. Especially his attempts to work out a synthesis of the various fields into one universal field, were not successful, despite the fact that he has done his very best to develop such a 'unified field theory'. This is clearly formulated in the following quotation from BERGMANN, 1942 :

" The general theory of relativity has furnished us with a logically unified theory of gravitation. But the electromagnetic field remains logically independent of the gravitational field :  the general theory of relativity has not succeeded in establishing a conceptual relationship between these two kinds of fields ... Furthermore, the general theory of relativity has failed to furnish us with a satisfactory theory of matter. In nature all particles belong to some type of elementary particle which has a characteristic mass, charge, etc. The theory of relativity, however, in which particles are mere singularities of the field, cannot explain why this is the case."

[Precisely here, we can see that, at least in many cases, natural science tries to dissolve concrete material  things  such that their very being and nature are merely derivatives of some universal entity (a field). Instead of things themselves and their natures it considers them as mere disturbances or sites of turbulence of, and in, some overall homogeneous entity which is the 'stuff of the world', sometimes an entity as empty as the 'space-time continuum'. On the other hand, natural philosophy, in the form of a first specification of Aristotelian metaphysics (i.e. the Aristotelian theory of Being), takes real and material beings as its point of departure. And these real beings are substances [in the metaphysical sense], meaning substances fully determined (up to the individual) by a set of 'accidents', i.e. by a set of  per se  and of  per accidens  determinations. Indeed, substances, so taken, are the very elements of Reality, where "element" here does not mean some basic constituent or particle, but a type of being to which all beings are ordered :  Aggregates of substances are merely  per accidens unities,  not themselves true beings like their constituent substances. But many aggregates are such as tending to become a single true substance, by, among other things, refusing 'alien' elements to make them up. Subatomic particles are considered by me [JB] to represent mere fragments of material beings. But they are, as to their nature (insofar as they possess one) ordered to make up atoms, the first true substances. And these atoms in turn are, as to their nature, ordered to make up higher-order substances, molecules and crystals. And molecules are in turn ordered to make up still higher-order substances, including organisms.
And it is especially HOENEN who empasizes the central role of "substance" in material reality, without disregarding important results obtained by natural science.]

With all this we have  concluded  the quote from, and the adding of comments to, ZWART, 1988, dealing with the aether and the theory of relativity.
We shall now continue again with the expositions of HOENEN, 1947.

In order to arrive at this denial [of the (substantiality of the) aether] Einstein reasons as follows  ( Die Naturwissenschaften IV, 1918, p. 701-702) :

"Gemäsz der speziellen Relativitätstheorie gab es keinen bevorzugten Bewegungszustand mehr. Dies bedeutete Leuchnung des Aethers im Sinne der früheren Theorien. Denn gab es einen Aether, so muszte er in jedem Raum-Zeitpunkt einen bestimmten Bewegungszustand haben, der in der Optik eine Rolle spielen muszte. Einen solchen bevorzugten Bewegungszustand aber gibt es nicht, wie die spezielle Relativitätstheorie lehrte, und darum gibt es auch keinen Aether im alten Sinne. Auch die allgemeine Relativitätstheorie kennt keinen bevorzugten Bewegungszustand in einem Punkte, den man etwa als Geschwindigkeit eines Aethers interpretieren könnte. Während aber nach der speziellen Relativitätstheorie ein Raumteil ohne Materie und ohne electromagnetisches Feld als schlechthin leer, d.h. durch keinerlei physikalischen Gröszen charakterisiert erscheint, hat nach der allgemeinen Relativitätstheorie auch der in diesem sinne leere Raum physikalische Qualitäten, welche durch die Komponenten des Gravitationspotentials [this is the potential energy with respect to the gravitational force] mathematisch karakterisiert sind, welche das metrische Verhalten dieses Raumteils sowie dessen Gravitationsfeld bestimmen. Man kann diesen Sachverhalt sehr wohl so auffassen, dasz man von einem Aether spricht, dessen Zustand von Punkt zu Punkt stetig variiert. Nur musz man sich davor hüten, diesem "Aether" stoffähnliche Eigenschaften (z.B. an jeder Stelle eine bestimmte Geschwindigkeit) zuzuschreiben."

( Note by HOENEN )  The last expression is imprecise. The following is meant :  A body cannot have a determined speed with respect to the parts of this aether. More precisely the intention of Einstein is given by M. Born in his book  Die Relativitätstheorie Einsteins, 2nd ed. Berlin 1921, p.168 n. :  "so gibt es in diesem 'Aether' keine fixierbaren Punkte und es ist sinnlos von Bewegung relativ zum Aether  zu sprechen."  ( Italics by HOENEN ).
English translation of the quotation :  "So in this aether there are no fixed points, and it doesn't make sense to speak of motion relative to the aether."

English translation and comment of the above quote from EINSTEIN, 1918 :

"According to the special theory of relativity there was no preferred state of motion anymore [See comment below]. This meant the denial of the aether in the sense of earlier theories. For if there were such an aether, then it had to have in every space-time point a determined state of motion, playng a part in optics. But there is no such preferred state of motion, as the special theory of relativity has teached us, and therefore there also is no aether in the old sense. Also the general theory of relativity does not know of a preferred state of motion in a point, [a state of motion] which one could interpret for example as velocity of an aether. While, however, according to the special theory of relativity, a part of space without matter and without electromagnetic field is simply empty, i.e. not to be characterized by any physical magnitudes,  the in this sense empty space, according to the general theory of relativity, also has physical qualities, which can mathematically be characterized by the components of the gravitational potential, which [qualities] determine the metric behavior of this part of space as well as its gravitational field. This state of things one may well take such that one speaks of an aether whose state continuously varies from point to point. But one must stay away from ascribing to this "aether" material features (for instance ascribing to every site a determined velocity)." [for this last expression, see the note above].

(Comment)  "No preferred motion" . . . "this meant the denial of the aether" :  In what state of motion - if there is any -- was the aether? It appeared very improbable that the aether was always moving together with the Earth (i.e. was 'carried along' with the earth), and accordingly it had to have a determined motion with respect to the Earth. And one could expect that that relative motion varied depending on the position of the Earth in its trajectory around the sun. Well, according to classical physics the propagation of every kind of wave-movement took place with a characteristic speed  with respect to the medium carrying the waves. To an observer who is in motion with respect to the medium (such as, for example, an observer on a sailing ship, studying the speed of the waves of the water) the speed of the waves carried by the medium must be different from that if he were at rest with respect to that medium. So one had to expect that the speed of light on Earth is different in different directions, depending on the direction and speed of the 'ether-wind' at the particular time and place in which the investigator finds himself. In investigating this, the result of the Michelson-Morley experiment, contrived for this purpose, was completely negative. No differences were detected. We therefore may hold that an 'aether-wind' cannot be observed [not necessarily implying that any sort of medium -- aether -- does not exist.].

Here we find, in what Einstein calls "empty space", the features mentioned above. This "space" has physical qualities, being measured by the components of the gravitational potential, [qualities] determining the gravitational field, [and] thus [these qualities] exerting physical influence on matter, and [these qualities] also determining the shape of the bodies physically. The "nothing" cannot possess this property and action, and thus this "empty space" is a really existing extensum [a spatial entity]. Now Einstein grants this extensum only the  name  aether, and not the thing anymore that earlier corresponded to that name, because this aether has no "stoffähnliche Eigenschaften" [features of matter, material features] -- (we might ask then :  Is, to an extensum, the possession of physical qualities, resulting in that extensum having influence on shape and motion of matter, not a "stoffähnliche Eigenschaft"? ) -- and especially it is said (because precisely that matters) :  This aether cannot have a determined velocity in every of its parts  [See the note of HOENEN given just above. The sentence should mean :  "So in this aether there are no fixed points and [therefore] it doesn't make sense to speak of motion relative to the aether." ].  Here, however, we run up against a contradiction.  A real extensum [surely] necessarily implies that its different parts, lying "extended" from each other, may successively being visited by a body. And then that body moves with a determined speed with respect to that aether.
Let us [JB] explain and interpret this as follows (figure and subscript) :

The aether, for convenience depicted as a one-dimensional extensum.
This extensum potentially is partitioned. An example of such partition is given.
A mass-particle is moving through this aether. It succesively makes contact with these (potential) parts, meaning that the particle is moving with respect to the aether. If the aether, viewed as 'naked' substance, is homogeneous (i.e. without actual and constant parts), then measurement of the motion of the particle cannot be done, because that demands an actual partition (regular or irregular) of the aether. But this does not necessarily imply that there isn't such a motion.

A physically real extensum not admitting this successive contact, carries a contradiction. Accordingly, this aether of Einstein is indeed the aether of Lorentz. Even suppose, that the aether of Einstein were not a substance, i.e. that the actually influencing qualities would not demand a substance as substrate whose qualities they are (what philosophically would be absurd), then, with respect to this field, which would be a really existing extensum, motion with a determined speed would still be possible. For all conditions from which this possibility necessarily derives, would be satisfied.
Assumptions of this kind have been expressly formulated, and it may be useful to dwell a little longer on these matters [In fact, HOENEN is now going to show in what way the concept of substance (in the metaphysical sense) has -- in the discussions about the aether -- been misunderstood by relying on the relevant expositions on substance of Kant and Descartes instead of on those of Aristotle.]
Reichenbach, one of the most acute members of the "Wiener Kreis", 1922, tells us :

" Man kann [mit Einstein] den Raum als aethererfüllt bezeichnen, denn er besitzt ja die physikalische Eigenschaft, den Messwerkzeugen eine bestimmte Gestalt zu geben un damit eine praktische Geometrie zu definieren. Nur hat dieser Aether nicht die Eigenschaft einer  Substanz,  dasz seine einzelnen Teile sich im Laufe der Zeit verfolgen lassen. Auf ihr ist der Bewegungsbegriff nicht anwendbar."

Translation :

" One may [with Einstein] view space as being filled with ether, because it [space] indeed possesses the physical property to impose upon the tools of measurement a certain shape, and thus with it to define a practical geometry. But the nature of this ether is not that of a  substance,  such that its individual parts could be continually observed [and passed by]. To it the concept of motion does not apply."

The same double thought-error [is seen here] :

• Something real (because it physically acts) that would not be or presuppose a substance [is absurd]. [Indeed, if something is acknowledged to be real, it is acknowledged to be a real being. Well, in material reality the only beings that are real are substances and accidents. If they are accidents, they presuppose substance.]
• The aether, supposed to be a real extensum without bringing with it the possibility of motion with respect to its parts [is absurd], even when not a substance.

" Die Gröszen, die man früher als Bestimmungsstücke des Aetherzustandes auffasste, die electrische und die magnetische Feldstärke, brauchen gar nicht "Eigenschaften" eines Mediums, einer beharrenden Substanz zu sein, sondern sie haben "selbständige" Existenz, obwohl sie in unaufhörlichem Wechsel, in stetem Entstehen und Vergehen begriffen sind.".

Translation :

" The magnitudes, earlier being considered as determining features of the aether-state, [namely] the electric and magnetic field intensity, do not at all need to be "properties" of a medium, of a persistent substance. They [the magnitudes] have "independent" existence, although they incessantly change, and undergoing continuous creation and destruction."

If indeed these properties themselves are taken to be substances, then already the smallest changes in intensity of a field would be substantial changes [i.e a transformations of one substance into another], which, moreover, would run through the field continuously. For them to be substantial changes is improbable. The supposed fact that substantial changes would spread across the field continuously, leads to an absurdity (that we shall not work out further here). What for our quest is again decisive is :  This real field is indeed an extensum [i.e. a spatially extended being] and as such brings with it the possibility of motion with respect to it.
These and the like misconceptions of the concept of substance [in its metaphysical sense] are so often encountered among physicists that we shall devote a few words to them. They [i.e. these misconceptions] concern the concept of substance, [ontologically] independent being, in general, and that of material independent being, matter (in the modern, i.e. physical, sense), specifically. They go back to definitions of Kant, formulating the accepted opinion in his century [namely "substance" taken only as that what persists].
According to the definitions of Kant, substance is that what persists in  all  changes in the world :  "bei allen Veränderungen in der Welt bleibt die  Substanz,  und nur die  Akzidenzen  wechseln". And he even asserts :  "in der Tat ist der Satz, dasz die Substanz beharrlich sei, tautologisch". Well, it is, of course true that there are many changes which are purely accidental, in which the substance itself remains what it was. We ourselves [as primary instance of a substance] can experience this in our own mental life :  thoughts and feelings change, the  " I ", my substance, remains, "beharrt". But aren't deeper changes possible? Aristotle's analysis, the study of  "becoming and corruption", teaches things better. It proves the  possibility  also of substantial change [as we see them in chemical reactions], without the need to suppose creation out of nothing. But it became the fate of Kant not knowing Aristotle and scholasticism. The pages themselves, from which we quoted, prove it. And what to Kant was fatal, no less it was to others too, before him, near him, and after him, up until our day.
This first principle :  all change is purely accidental, substantial change rules out, substance is that what remains the same in all change,  is falsh.
This so-called principle of substance now becomes, in the case of material substance, aggravated [For HOENEN a material substance = an inorganic physical(intrinsic) body]. According to mechanistic philosophy also accidental  intrinsic  change, for example changes in quality, is impossible. What remains of explaining the change in the world is movement of unchangeable particles. Accordingly, as to change, material substance is precisely that what exclusively admits motion, [exclusively admits] what is mobile in space. So does Kant in many places in his  Metaphysische Anfangsgründe der Naturwissenschaft.
In our days this concept of substance is, as a result of the collapse of the mechanistic view of Nature -- about which we will speak later -- not only with respect to the aether, but also to ordinary matter, now in troubled water.
And see the consequences of a false principle :  Since Nature and her properties no longer can be explained exclusively by motion -- for the aether, think of the theory of Lorentz, making it immobile [So the changes in and of the aether are not constituted by movements, but are qualitative changes only], and [think] of the qualities of [i.e. supposed by] Einstein [attributed to the aether] -- matter is [said to be] no material substance anymore, because it is not, or not exclusively, mobile in space. Let us hear how Bavink, 1935, describes this crisis :

" Was die Materie sicher nicht is, das ist jener Haufen "Starrer Wirklichkeitsklötzchen" als den der ältere materialistische Mechanismus sie betrachted hat. Atome und auch ihre elementarbestandteile : Protonen, Electronen, usw. sind ganz bestimmt nicht "Substanzen" in dem Sinne, dass sie als raumerfüllende, zeitlich aber unveränderliche Gegebenheiten in alle Ewigkeit mit sich identisch bleiben, so dass alles Naturgeschehen nur im einem Umordnen dieser einfürallemal gegebene Elementarteilchen bestünde ... Darüber sind sich jedenfalls heute alle genaueren Kenner der modernen Physik mit wenigen Ausnahmen einig, dass der alte primitive Substanzbegriff nicht zu halten ist. Leider können wir, wie schon bemerkt, nur nicht präzis heute sagen, was eigentlich an seine Stelle zu treten hat. Das soll ja erst noch herausgefunden werden."

" What matter certainly not is, is that heap of "stiff reality-lumps" as it was viewed by the old [school of] materialistic Mechanism. Atoms, and also their elementary constituents :  protons, electrons, etc., are definitely not "substances" in the sense that they, as space-filling but temporally unchangeable data, remain identical in themselves, so that all of the natural events consisted exclusively in re-arranging these once-and-for-all-given elementary particles ... At least today all experts of modern physics, with few exceptions, agree that the ancient primitive concept of substance must be rejected. Unfortunately today we, as already noted, cannot say precisely by what it should be replaced. That still awaits discovery."

That "ancient primitive concept of substance" was the substance of the Eleates and Democritus, re-introduced by the modern mechanistic philosophy of Descartes and taken over by Kant and the moderns. But this primitve concept already was superseded by Aristotle's philosophy of  "Generation and Corruption". By what that primitive concept of substance should be replaced doesn't need to be discovered -- "herausgefunden" -- anymore. It is known since Aristotle, worked out in grand fashion by the great medieval masters, and merely awaits application.
Only this erroneous concept of substance is the cause of denial of the substantial aether of Lorentz. For only when the erroneous concepts of substance are presupposed, one comes to deny  the nature of being-a-substance  of the aether of the general theory of relativity and that of the electromagnetic field theory.
An example is seen even in so acute a thinker as H. Weyl. In his book  Philosophie der Mathematik und Naturwissenschaft (p.143) he describes the development of the modern concept of aether from Huygens to Einstein. He divides this history in three episodes or phases.
First of all we have the aether [as viewed] from Huygens up to and including Fresnel (and subsequent authors in his trail). This [proposed type of ] aether is viewed as a very rarefied ordinary body to which an atomistic structure is usually attributed. It is the carrier of light-vibrations, taken as ordinary mechanical displacements. This aether has a "substantial-physical nature". One sees :  because the aether particles can be moved, and no other change being permitted, the aether is [taken to be] a substance. It loses this nature as soon as those mechanical vibrations are replaced by other, qualitative changes. As soon as, from the hands of Faraday and Maxwell, the theory of electromagnetic fields was developed, and [as soon as] became clear that also the optical [i.e. with respect to visible electromagnetic radiation - light] phenomena turned out to come under this theory, "entkleidet sich der Aether seines substantiell-physischen Characters, und es bleibt nichts weiter zurück denn der absolute Raum als Medium der electromagnetischen Feldzustände."
Translation :  "the aether disposes itself of its substantial-physical nature, and nothing is left than absolute space to fulfill the function of medium of electromagnetic field states."
( Weyl only presents a very schematic overview and doesn't therefore speak about how, in the beginning, those electromagnetic field states were still considered to be mechanical displacements, by Faraday, by Maxwell, by Kelvin, by tutti quanti, until with Hertz and Lorentz mechanical representations were definitively rejected ). This is the aether of Lorentz, of which Weyl denies the substantial nature, because now we do not have a mechanical aether anymore :  Indeed, very consistent with the above described principles of substance of [the school of ] mechanicism and of Kant, but also very unphilosophically. Lorentz himself was judging more acutely and more correctly. He viewed his aether as a substantial aether.
The third phase [of the four phases of Weyl] is that of the special theory of relativity, and this "macht ... dem substantiellen Aether vollends den Garaus" (= "finally kills off the substantial ether").
Finally, there is the fourth phase, that of the general theory of relativity, in which the aether at the same time has become : (deformable) gravitational field and electromagnetic field. And now, according to our author [Weyl ], the aether has "seinen physischen Character zurückgewonnen" (= "gotten back its physical nature") (we assume as a result of this deformation), but it nevertheles is not that anymore what it originally was, "wo er als substantielles Medium auf den Plan tritt" [= "where it appears as substantial medium"]. That here the notion  material substance  is being used in the erroneous sense of the mechanicistic world view is clear. Anyway, Weyl does the same on earlier pages of this book, where he deals with "matter". Yet, there he presents the excellent description of the relationship of (ponderable) matter with the field :  " Die Materie ist das  felderregende Agens,  das Feld ein extensives Medium, das vermöge seiner in den Feldgesetzen zum Ausdruck kommenden Struktur die wirkung von Körper zu Körper überträgt" (= " Matter is the field-generating agent, [and] the field [is an] extensive medium, which, as a result of its structure, expressed by its field-laws, transfers action from body to body."). But this extensional medium which is not nothing, relates to the structure which is qualitative, as the  " I "  relates to my thoughts and feelings, as a substance to its accidents. This is still the true aether of Lorentz, as is demanded by the metaphysical principles of Aristotle, a substance which is extensional and substrate of qualitative changes, not an Eleatic-Democritean-Cartesian substance, but substance nevertheless. And our Lorentz, who was not a philosopher, but simply was very acute, had seen things correctly when he called this aether a substantial aether. [Thematically, we must view the field as an extensive substance having a quality, which is its structure. This field, then, is the aether. Or we must view the field as a qualitative variable determination of the aether which itsef is a substance carrying the field.]

To summarize things :  The aether of Lorentz still exists as a real -- because active and passive -- extensum, which is sufficient for it to be seen as a general medium of localization. The parts of the aether satisfy the conditions demanded by Aristotle for the notion of place :  They are extensa, they are real, they are something different from that what is placed, in immediate contact with the latter, and finally immobile. These parts satisfy these conditions just as perfectly as does the immediately surrounding surface, taken to be "place" by Aristotle. The last two conditions are even better satisfied :  The contact is an "intrinsic" contact, and the parts of the aether are absolutely, not merely formally, immobile.
The fact that many modern physicists do not classify this aether as a substance, leaves, firstly, the aether as medium of localization unaffected, and, secondly, is merely a consequence of an incorrect notion of material substance, in which we cannot follow them.

To be continued in next document

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