are so constituted as to find the same sort of natural phenomena. The realm of the physical phenomena, whatever inner Being may be behind it, is, for us, primarily this common realm of human experience. Upon this consideration the very definition of what we call Nature depends.
It is, of course, true that any one of us, when alone,
supposes himself to be still in the presence of Nature. It
is also true that this supposition would lose its present
meaning just as soon as we supposed not only that we were
alone with Nature, but that, even if our fellows had the
same opportunities as ourselves, they would still be wholly
unable to verify our observations. A nature that is not
only by accident observable just now to me alone, but
that also is such that nobody else amongst all men
besides myself can observe it, becomes, at once, to my mind,
either one of two things, viz. either something that is
explicitly my own dream, or fancy, or hallucination, or
other mental state, or else something that I should view,
if I continued to believe in it, as a reality belonging to
a realm of spirits, whom I might then suppose to exist
apart from men. In either case, such fact, observable by
me alone, is no longer to be conceived as belonging to
the well-known material world of common sense and of
science.
III
Our belief in Man, then, is logically prior to our interpretation of Nature. And any theory of Nature must undertake to explain, not merely how these data of sense appear to any one of us in this order, and subject to these valid laws, but how all men come to possess this