"Sorrow is hard to bear, and doubt is slow to clear.
Each sufferer says his say, his scheme of the weal and woe:
But God has a few of us whom he whispers in the ear;
The rest may reason and welcome: 'tis we musicians know."[A]

[Footnote A: _Abt Vogler_.]

And side by side with the poetry that grasps the truth in immediate
intuition, there is also the uniting activity of philosophy, which,
catching up its hints, carries "back our scattered knowledge of the
facts and laws of nature to the principle upon which they rest; and, on
the other hand, develops that principle so as to fill all the details of
knowledge with a significance which they cannot have in themselves, but
only as seen _sub specie aeternitatis_."[B]

[Footnote B: _The Problem of Philosophy at the Present Time_, by
Professor Caird.]

So far we have spoken of the function of philosophy in the
interpretation of the phenomena of the outer world. It bears witness to
the unity of knowledge, and strives by the constructive criticism of the
categories of science to render that unity explicit. Its function is, no
doubt, valid and important, for it is evident that man cannot rest
content with fragmentary knowledge. But still, it might be objected that
it is premature at present to endeavour to formulate that unity.
Physics, chemistry, biology, and the other sciences, while they
necessarily presuppose the unity of knowledge, and attempt in their own
way and in their own sphere to discover it, are making very satisfactory
headway without raising any of the desperate questions of metaphysics as
to its ultimate nature. For them it is not likely to matter for a long