Physics   

Example: A man is engaged in collecting subscriptions for a feast. He
would have gone to such and such a place for the purpose of getting
the money, if he had known. He actually went there for another purpose
and it was only incidentally that he got his money by going there; and
this was not due to the fact that he went there as a rule or
necessarily, nor is the end effected (getting the money) a cause
present in himself-it belongs to the class of things that are
intentional and the result of intelligent deliberation. It is when
these conditions are satisfied that the man is said to have gone 'by
chance'. If he had gone of deliberate purpose and for the sake of
this-if he always or normally went there when he was collecting
payments-he would not be said to have gone 'by chance'.
It is clear then that chance is an incidental cause in the sphere of
those actions for the sake of something which involve purpose.
Intelligent reflection, then, and chance are in the same sphere, for
purpose implies intelligent reflection.
It is necessary, no doubt, that the causes of what comes to pass by
chance be indefinite; and that is why chance is supposed to belong to
the class of the indefinite and to be inscrutable to man, and why it
might be thought that, in a way, nothing occurs by chance. For all
these statements are correct, because they are well grounded. Things
do, in a way, occur by chance, for they occur incidentally and chance
is an incidental cause. But strictly it is not the cause-without
qualification-of anything; for instance, a housebuilder is the cause
of a house; incidentally, a fluteplayer may be so.
And the causes of the man's coming and getting the money (when he did
not come for the sake of that) are innumerable. He may have wished to
see somebody or been following somebody or avoiding somebody, or may
have gone to see a spectacle. Thus to say that chance is a thing
contrary to rule is correct. For 'rule' applies to what is always true
or true for the most part, whereas chance belongs to a third type of
event. Hence, to conclude, since causes of this kind are indefinite,
chance too is indefinite. (Yet in some cases one might raise the
question whether any incidental fact might be the cause of the chance
occurrence, e.g. of health the fresh air or the sun's heat may be the
cause, but having had one's hair cut cannot; for some incidental
causes are more relevant to the effect than others.)
Chance or fortune is called 'good' when the result is good, 'evil'
when it is evil. The terms 'good fortune' and 'ill fortune' are used
when either result is of considerable magnitude. Thus one who comes
within an ace of some great evil or great good is said to be fortunate
or unfortunate. The mind affirms the essence of the attribute,
ignoring the hair's breadth of difference. Further, it is with reason
that good fortune is regarded as unstable; for chance is unstable, as
none of the things which result from it can be invariable or normal.
Both are then, as I have said, incidental causes-both chance and
spontaneity-in the sphere of things which are capable of coming to
pass not necessarily, nor normally, and with reference to such of
these as might come to pass for the sake of something.
Part 6
They differ in that 'spontaneity' is the wider term. Every result of
chance is from what is spontaneous, but not everything that is from
what is spontaneous is from chance.
Chance and what results from chance are appropriate to agents that are
capable of good fortune and of moral action generally. Therefore
necessarily chance is in the sphere of moral actions. This is
indicated by the fact that good fortune is thought to be the same, or
nearly the same, as happiness, and happiness to be a kind of moral
action, since it is well-doing. Hence what is not capable of moral
action cannot do anything by chance. Thus an inanimate thing or a
lower animal or a child cannot do anything by chance, because it is
incapable of deliberate intention; nor can 'good fortune' or 'ill
fortune' be ascribed to them, except metaphorically, as Protarchus,
for example, said that the stones of which altars are made are