s is the fundamental assumption of
science. Many things have not yet been explained, but there is an
explanation for everything; of that every thinker feels perfectly sure.
"Fifty years ago," says Sir John Lubbock, "the Book of Nature was like
some richly illuminated missal, written in an unknown tongue; of the
true meaning little was known to us; indeed we scarcely realized that
there was a meaning to decipher. Now glimpses of the truth are gradually
revealing themselves; we perceive that there is a reason--and in many
cases we know what that reason is--for every difference in form, in
size, and in color, for every bone and feather, almost for every
hair."[6]

This is the latest word of the latest philosophy; there is a reason for
everything. As Romanes says, Nature is instinct with reason; "tap her
where you will, reason oozes out at every pore."

If all things are rational and intelligible, then all things must be
the product of a rational Intelligence. That conclusion seems
inevitable.

But we can go further than this. It is not merely true that we can find
in the world about us the signs of an Intelligence like our own, it is
also true that our own intelligence has been developed by the revelation
to us of this Intelligence in the world about us. "If," says Walker,
"human reason is but 'the reflection in us of the universe outside of
us,' then, clearly, the Reason was there, expressed in the universe,
before it possibly could be reflected in us. It is _our relation to the
Universe that makes us rational_." And again, "Apart from the Reason
expressed in the Universe around him, man could never have become the
rational being that he is."[7]

This, then, is the first great reason why our religion has gradually
become more rational. The rationality of the universe constantly
presented to our thought has developed a rationality in our thoughts
about the universe. The mind, like the dyer's hand, is subdued to what
it works in. The response of primitive man to the pressure of Nature
upon him was a response of wonder and awe and fear; his religion was
instructive, emotional; but through the long tuition of the ages, the
old nurse has taught him how to use his reason; and he now finds unity
where he once found strife, and order and law where once confusion and
chaos reigned. His religion has become rational.

But what do we mean when we say that man's great teacher has been
Nature? Nature, as we have seen, is instinct