Physics   

which denied chance), nevertheless they speak of some of these things
as happening by chance and others not. For this reason also they ought
to have at least referred to the matter in some way or other.
Certainly the early physicists found no place for chance among the
causes which they recognized-love, strife, mind, fire, or the like.
This is strange, whether they supposed that there is no such thing as
chance or whether they thought there is but omitted to mention it-and
that too when they sometimes used it, as Empedocles does when he says
that the air is not always separated into the highest region, but 'as
it may chance'. At any rate he says in his cosmogony that 'it happened
to run that way at that time, but it often ran otherwise.' He tells us
also that most of the parts of animals came to be by chance.
There are some too who ascribe this heavenly sphere and all the worlds
to spontaneity. They say that the vortex arose spontaneously, i.e. the
motion that separated and arranged in its present order all that
exists. This statement might well cause surprise. For they are
asserting that chance is not responsible for the existence or
generation of animals and plants, nature or mind or something of the
kind being the cause of them (for it is not any chance thing that
comes from a given seed but an olive from one kind and a man from
another); and yet at the same time they assert that the heavenly
sphere and the divinest of visible things arose spontaneously, having
no such cause as is assigned to animals and plants. Yet if this is so,
it is a fact which deserves to be dwelt upon, and something might well
have been said about it. For besides the other absurdities of the
statement, it is the more absurd that people should make it when they
see nothing coming to be spontaneously in the heavens, but much
happening by chance among the things which as they say are not due to
chance; whereas we should have expected exactly the opposite.
Others there are who, indeed, believe that chance is a cause, but that
it is inscrutable to human intelligence, as being a divine thing and
full of mystery.
Thus we must inquire what chance and spontaneity are, whether they are
the same or different, and how they fit into our division of causes.
Part 5
First then we observe that some things always come to pass in the same
way, and others for the most part. It is clearly of neither of these
that chance is said to be the cause, nor can the 'effect of chance' be
identified with any of the things that come to pass by necessity and
always, or for the most part. But as there is a third class of events
besides these two-events which all say are 'by chance'-it is plain
that there is such a thing as chance and spontaneity; for we know that
things of this kind are due to chance and that things due to chance
are of this kind.
But, secondly, some events are for the sake of something, others not.
Again, some of the former class are in accordance with deliberate
intention, others not, but both are in the class of things which are
for the sake of something. Hence it is clear that even among the
things which are outside the necessary and the normal, there are some
in connexion withwhich the phrase 'for the sake of something' is
applicable. (Events that are for the sake of something include
whatever may be done as a result of thought or of nature.) Things of
this kind, then, when they come to pass incidental are said to be 'by
chance'. For just as a thing is something either in virtue of itself
or incidentally, so may it be a cause. For instance, the housebuilding
faculty is in virtue of itself the cause of a house, whereas the pale
or the musical is the incidental cause. That which is per se cause of
the effect is determinate, but the incidental cause is indeterminable,
for the possible attributes of an individual are innumerable. To
resume then; when a thing of this kind comes to pass among events
which are for the sake of something, it is said to be spontaneous or
by chance. (The distinction between the two must be made later-for the
present it is sufficient if it is plain that both are in the sphere of
things done for the sake of something.)