f an end. Therefore it is necessary that there should be
habits.

_I answer that,_ As we have said above (AA. 2, 3), habit implies a
disposition in relation to a thing's nature, and to its operation or
end, by reason of which disposition a thing is well or ill disposed
thereto. Now for a thing to need to be disposed to something else,
three conditions are necessary. The first condition is that which is
disposed should be distinct from that to which it is disposed; and
so, that it should be related to it as potentiality is to act.
Whence, if there is a being whose nature is not composed of
potentiality and act, and whose substance is its own operation, which
itself is for itself, there we can find no room for habit and
disposition, as is clearly the case in God.

The second condition is, that that which is in a state of
potentiality in regard to something else, be capable of determination
in several ways and to various things. Whence if something be in a
state of potentiality in regard to something else, but in regard to
that only, there we find no room for disposition and habit: for such
a subject from its own nature has the due relation to such an act.
Wherefore if a heavenly body be composed of matter and form, since
that matter is not in a state of potentiality to another form, as we
said in the First Part (Q. 56, A. 2) there is no need for disposition
or habit in respect of the form, or even in respect of operation,
since the nature of the heavenly body is not in a state of
potentiality to more than one fixed movement.

The third condition is that in disposing the subject to one of those
things to which it is in potentiality, several things should occur,
capable of being adjusted in various ways: so as to dispose the
subject well or ill to its form or to its operation. Wherefore the
simple qualities of the elements which suit the natures of the
elements in one single fixed way, are not called dispositions or
habits, but "simple qualities": but we call dispositions or habits,
such things as health, beauty, and so forth, which imply the
adjustment of several things which may vary in their relative
adjustability. For this reason the Philosopher says (Metaph. v, text.
24, 25) that "habit is a disposition": and disposition is "the order
of that which has parts either as to place, or as to potentiality, or
as to species," as we have said above (A. 1, ad 3). Wherefore, since
there are many things for whose natures and