. The only way in
which Aristotle could have surmounted these difficulties would have
been to prove that sensation is a development of reason which goes
beyond nutrition. And he could only do this by showing that sensation
logically arises out of nutrition. For a logical development is the
same as a rational development. He ought to have logically deduced
sensation from nutrition, and so with all the other forms. As it is,
all that can be said is that Aristotle was the founder of a philosophy
of evolution because he saw that evolution implies movement towards an
end, and because he attempted to point out the different stages in the
attainment of that end, {338} but that he failed rationally to develop
the doctrine stage by stage.

As neither the principle of form in general was shown to be necessary,
nor were the particular forms deduced from each other, we have to
conclude that Aristotle like Plato, _named_ a self-explanatory
principle, reason or form, as ultimate principle of things, but failed
to show in detail that it is self-explanatory. Yet, in spite these
defects, the philosophy of Aristotle is one of the greatest
philosophies that the world has ever seen, or is ever likely to see.
If it does not solve all problems, it does render the world more
intelligible to us than it was before.

{339}

CHAPTER XIV

THE GENERAL CHARACTER OF POST-ARISTOTELIAN PHILOSOPHY

The rest of the story of Greek philosophy is soon told, for it is the
story of decay. The post-Aristotelian is the least instructive of the
three periods of Greek thought, and I shall delineate only its main
outlines.

The general characteristics of the decay of thought which set in after
Aristotle are intimately connected with the political, social, and
moral events of the time. Although the huge empire of Alexander had
broken up at the conqueror's death, this fact had in no way helped the
Greek States to throw off the yoke of their oppressors. With the
single exception of Sparta, which stubbornly held out, they had
become, for all intents and purposes, subject to the dominion of
Macedonia. And the death of Alexander did not alter this fact. It was
not merely that rude might had overwhelmed a beautiful and delicate
civilization. That civilization itself was decaying. The Greeks had
ceased to be a great and free people. Their vitality was ebbing. Had
it not been one conqueror it would have been another. They were
growing old. They had to give way