Capítulo 11. Chapter XI.—Concerning Increase And Decrease
[3.11.82] Employing the same reasoning we suspend judgement also concerning both increase and decrease. For the outward evidence[397] seems to support their reality, which the arguments seem to refute. For just consider: That which increases must grow in size as a stable substance, so that it will be false for anyone to say that one thing increases when an addition is made to another. Since then substance[398] is never stable but always in flux, one part supplanting another, the thing said to have increased does not retain its former substance together with the added substance but has its substance all different.
[3.11.83] Just as if, for example, when there is a beam three cubits long a man should bring another of ten cubits and declare that the beam of three cubits had increased, he would be lying because the one is wholly different from the other; so too in the case of every object which is said to increase, as the former matter flows away and fresh matter enters in its place, if what is said to be added is added, one should not call such a condition increase but complete alteration.
[3.11.84] The same argument applies also to decrease.[399] For how could that which has no stable existence be said to have decreased? Besides, if decrease takes place by way of subtraction, and increase by addition, and neither subtraction nor addition is anything, then neither decrease nor increase is anything.