n the contrary, in replying thus, I conceive that
I am simply honest and truthful, and show a proper regard for the
economy of time. So Hume's strong and subtle intellect takes up a great
many problems about which we are naturally curious, and shows us that
they are essentially questions of lunar politics, in their essence
incapable of being answered, and therefore not worth the attention of
men who have work to do in the world. And he thus ends one of his
essays:--

"If we take in hand any volume of Divinity, or school metaphysics, for
instance, let us ask, _Does it contain any abstract reasoning concerning
quantity or number?_ No. _Does it contain any experimental reasoning
concerning matter of fact and existence?_ No. Commit it then to the
flames; for it can contain nothing but sophistry and illusion."[55]

Permit me to enforce this most wise advice. Why trouble ourselves about
matters of which, however important they may be, we do know nothing, and
can know nothing? We live in a world which is full of misery and
ignorance, and the plain duty of each and all of us is to try to make
the little corner he can influence somewhat less miserable and somewhat
less ignorant than it was before he entered it. To do this effectually
it is necessary to be fully possessed of only two beliefs: the first,
that the order of Nature is ascertainable by our faculties to an extent
which is practically unlimited; the second, that our volition[56] counts
for something as a condition of the course of events.

Each of these beliefs can be verified experimentally, as often as we
like to try. Each, therefore, stands upon the strongest foundation upon
which any belief can rest, and forms one of our highest truths. If we
find that the ascertainment of the order of nature is facilitated by
using one terminology, or one set of symbols, rather than another, it is
our clear duty to use the former; and no harm can accrue, so long as we
bear in mind that we are dealing merely with terms and symbols.

In itself it is of little moment whether we express the phenomena of
matter in terms of spirit; or the phenomena of spirit in terms of
matter: matter may be regarded as a form of thought, thought may be
regarded as a property of matter--each statement has a certain relative
truth. But with a view to the progress of science, the materialistic
terminology is in every way to be preferred. For it connects thought
with the other phenomena of the universe,