f the past, that the
historian can see the true perspective, and can penetrate the
relations of each great man to the time in which he lived. Plato was
the founder of idealism, and his idealism was in many respects crude
and untenable. It was the special mission of Aristotle to clear away
these crudities, and so develop Platonism into a tenable philosophy.
And it was natural that he should emphasize the crudities, which he
had to fight so hard to overcome, rather than that substratum of truth
which Plato had already developed, and which therefore required no
special treatment at his hands. It was the differences between himself
and his predecessor which were most obvious to him, and it was
inevitable that he should adopt a thoroughly polemical attitude
towards his master.

But if the agreement was more deep-seated than the differences, and
lay in the recognition of the Idea as the {257} absolute foundation of
the world, the differences were none the less very striking. In the
first place, Aristotle loved facts. What he wanted was always definite
scientific knowledge. Plato, on the other hand, had no love of facts
and no gift for physical enquiries. And what disgusted Aristotle about
the system of Plato was the contempt which it poured upon the world of
sense. To depreciate objects of sense, and to proclaim the knowledge
of them valueless, was a fundamental characteristic of all Plato's
thinking. But the world of sense is the world of facts, and Aristotle
was deeply interested in facts. No matter in what branch of knowledge,
any fact was received by Aristotle with enthusiasm. To Plato it
appeared of no interest what the habits of some obscure animal might
be. That alone which should be pursued is the knowledge of the Idea.
And he went so far as to deny that knowledge of the sense-world could
properly be described as knowledge at all. But the habits of animals
appeared to Aristotle a matter worthy of investigation for its own
sake. Francis Bacon in his "Novum Organum" has many contemptuous
references to Aristotle. And the gist of them all is that Aristotle
had no regard for facts, but theorized a priori out of his head, and
that instead of patiently investigating the facts of nature, he
decided, upon so-called "rational" grounds, what nature ought to do,
and squared the facts with his theories.

It was natural for Bacon to be unjust to him. He, with the other
thinkers of his time, was engaged upon an uphill fight agains