In a formula like X = X + 1, that we can encounter in computer science, X should have the same value on either side of " = ", implying that we would get for, say, X = 5, 5 = 5 + 1, and this seems to result in a contradiction, which would force us to deny the Species-Individuum Structure universally for mathematical formulas.

But in the present case it concerns in fact a prescription, namely that 1 should be added to the value of X.

Hence the formula X = X + 1 means X_{N + 1} = X_{N} + 1.

Verbally this is **:** " The new X becomes the old X plus one", implying that we don't have to do with __one__, but with __two__ different symbols, namely X_{N + 1} and X_{N}. So no symbol is repeated in this case.