wledge 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
time to come whether Optimism or Pessimism, Materialism or Idealism, or
none of them, be true. In any case the principles they establish are
valid. Physical relations always remain true; "ginger will be hot i' the
mouth, and there will be more cakes and ale." It is only when the
sciences break down beneath the weight of knowledge and prove themselves
inadequate, that it becomes necessary or advantageous to seek for more
comprehensive principles. At present is it not better to persevere in
the way of science, than to be seduced from it by the desire to solve
ultimate problems, which, however reasonable and pressing, seem to be
beyond our power to answer?

Such reasonings are not convincing; still, so far as natural science is
concerned, they seem to indicate that there might be no great harm in
ignoring, for a time, its dependence on the wider aspects of human
thought. There is no department of nature so limited, but that it may
more than satisfy the largest ambition of the individual for knowledge.
But this attitude of indifference to ultimate questions is liable at any
moment to be disturbed.

"Just when we are safest, there's a sunset-touch,
A fancy from a flower-bell, some one's death,
A chorus-ending from Euripides,--
And that's enough for fifty hopes and fears
As old and new at once as nature's self,
To rap and knock and enter in our soul,
Take hands and dance there, a fantastic rin