ll knowledge," said the Platonists, "is the gathering up
into one."[460]

[Footnote 459: Cudworth's "Intellectual System," vol. i. p. 518.]

[Footnote 460: Hamilton's "Metaphysics," vol. i. pp. 67-70 (English
edition).]

Starting from this fundamental idea, _that, beneath the endless flux and
change of the visible universe, there must be a permanent principle of
unity_, we have seen developed two opposite schools of speculative
thought. As the traveller, standing on the ridges of the Andes, may see
the head-waters of the great South American rivers mingling in one, so
the student of philosophy, standing on the elevated plane of analytic
thought, may discover, in this fundamental principle, the common source
of the two great systems of speculative thought which divided the
ancient world. Here are the head-waters of the sensational and the
idealist schools. The Ionian school started its course of inquiry in the
direction of _sense_; it occupied itself solely with the phenomena of
the external world, and it sought this principle of unity in a
_physical_ element. The Italian school started its course of inquiry in
the direction of _reason_; it occupied itself chiefly with rational
conceptions or _a priori_ ideas, and it sought this principle of unity
in purely _metaphysical_ being. And just as the Amazon and La Plata
sweep on, in opposite directions, until they reach the extremities of
the continent, so these two opposite streams of thought rush onward, by
the force of a logical necessity, until they terminate in the two
Unitarian systems of _Absolute Materialism_ and _Absolute Idealism_,
and, in their theological aspects, in a pantheism which, on the one
hand, identifies God with matter, or, on the other hand, swallows up the
universe in God.

The radical error of both these systems is at once apparent. The
testimony of the primary faculties of the mind was not regarded as each,
within its sphere, final and decisive. The duality of consciousness was
not accepted in all its integrity; one school rejected the testimony of
reason, the other denied the veracity of the senses, and both prepared
the way for the _skepticism_ of the Sophists.

We must not, however, lose sight of the fact that there were some
philosophers of the pre-Socratic school, as Anaxagoras and Empedocles,
who recognized the partial and exclusive character of both these
systems, and sought, by a method which Cousin would designate as
Eclecticism, to com