Shall we have to admit that composition and decomposition are
movements which exist by themselves, and analyze alteration into them?
Condensation is explained as undergoing an alteration; that means, as
becoming composite. On the other hand, rarefaction is also explained
as undergoing an alteration, namely, that of decomposition; when, for
instance, one mingles water and wine, each of these two things becomes
other than it was, and it is the composition which has operated the
alteration. We will answer that here composition and decomposition no
doubt precede certain alterations, but these alterations are something
different than compositions and decompositions. Other alterations
(certainly) are not compositions and decompositions, for neither can
condensation nor rarefaction be reduced to these movements, nor are
they composed of them. Otherwise, it would be necessary to acknowledge
the (existence of) emptiness. Besides, how could you explain blackness
and whiteness, as being composed of composition and decomposition?
This doctrine would destroy all colors and qualities, or at least,
the greater part of them; for if all alteration, that means, all
change of quality, consisted in a composition or decomposition, the
result would not be the production of a quality, but an aggregation or
disaggregation. How indeed could you explain the movements of teaching
and studying by mere "composition"?