intellect. Our accurate records of the operations of nature extend
through only two or three centuries, and do not reach a
satisfactory standard until within a single century. The
experience of the individual is limited to a few years, and beyond
this period he must depend upon the records of his ancestors. All
his knowledge of the laws of nature is derived from this very
limited experience. How can he essay to describe what may have
been going on hundreds of millions of years in the past? Can he
dare to say that nature was the same then as now?

It is a fundamental principle of the theory of evolution, as
developed by its greatest recent expounder, that matter itself is
eternal, and that all the changes which have taken place in the
universe, so far as made up of matter, are in the nature of
transformations of this eternal substance. But we doubt whether
any physical philosopher of the present day would be satisfied to
accept any demonstration of the eternity of matter. All he would
admit is that, so far as his observation goes, no change in the
quantity of matter can be produced by the action of any known
cause. It seems to be equally uncreatable and indestructible. But
he would, at the same time, admit that his experience no more
sufficed to settle the question than the observation of an animal
for a single day would settle the question of the duration of its
life, or prove that it had neither beginning nor end. He would
probably admit that even matter itself may be a product of
evolution. The astronomer finds it difficult to conceive that the
great nebulous masses which he sees in the celestial spaces--
millions of times larger than the whole solar system, yet so
tenuous that they offer not the slightest obstruction to the
passage of a ray of light through their whole length--situated in