Meteorology By Aristotle

BOOK IV

Part 1

We have explained that the qualities that constitute the elements
are four, and that their combinations determine the number of the
elements to be four.

Two of the qualities, the hot and the cold, are active; two, the dry
and the moist, passive. We can satisfy ourselves of this by looking
at instances. In every case heat and cold determine, conjoin, and
change things of the same kind and things of different kinds, moistening,
drying, hardening, and softening them. Things dry and moist, on the
other hand, both in isolation and when present together in the same
body are the subjects of that determination and of the other affections
enumerated. The account we give of the qualities when we define their
character shows this too. Hot and cold we describe as active, for
'congregating' is essentially a species of 'being active': moist and
dry are passive, for it is in virtue of its being acted upon in a
certain way that a thing is said to be 'easy to determine' or 'difficult
to determine'. So it is clear that some of the qualities are active
and some passive.

Next we must describe the operations of the active qualities and the
forms taken by the passive. First of all, true becoming, that is,
natural change, is always the work of these powers and so is the corresponding
natural destruction; and this becoming and this destruction are found
in plants and animals and their parts. True natural becoming is a
change introduced by these powers into the matter underlying a given
thing when they are in a certain ratio to that matter, which is the
passive qualities we have mentioned. When the hot and the cold are
masters of the matter they generate a thing: if they are not, and
the failure is partial, the object is imperfectly boiled or otherwise
unconcocted. But the strictest general opposite of true becoming is
putrefaction. All natural destruction is on the way to it, as are,
for instance, growing old or growing dry. Putrescence is the end of
all these things, that is of all natural objects, except such as are
destroyed by violence: you can burn, for instance, flesh, bone, or
anything else, but the natural course of their destruction ends in
putrefaction. Hence things that putrefy begin by being moist and end
by being dry. For the moist and the dry were their matter, and the
operation of the active qualities caused the dry to be determined
by the moist.