and I reply that I do not know; that neither I, nor any one else, has
any means of knowing; and that, under these circumstances, I decline to
trouble myself about the subject at all; I do not think he has any right
to call me a sceptic. On 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