ays to move: the perception of ideas being (as I
conceive) to the soul, what motion is to the body; not its essence, but
one of its operations. And therefore, though thinking be supposed never
so much the proper action of the soul, yet it is not necessary to
suppose that it should be always thinking, always in action. That,
perhaps, is the privilege of the infinite Author and Preserver of all
things, who "never slumbers nor sleeps"; but is not competent to any
finite being, at least not to the soul of man. We know certainly, by
experience, that we SOMETIMES think; and thence draw this infallible
consequence,--that there is something in us that has a power to think.
But whether that substance PERPETUALLY thinks or no, we can be no
further assured than experience informs us. For, to say that actual
thinking is essential to the soul, and inseparable from it, is to beg
what is in question, and not to prove it by reason;--which is necessary
to be done, if it be not a self-evident proposition But whether this,
"That the soul always thinks," be a self-evident proposition, that
everybody assents to at first hearing, I appeal to mankind. It is
doubted whether I thought at all last night or no. The question being
about a matter of fact, it is begging it to bring, as a proof for it,
an hypothesis, which is the very thing in dispute: by which way one may
prove anything, and it is but supposing that all watches, whilst the
balance beats, think, and it is sufficiently proved, and past doubt,
that my watch thought all last night. But he that would not deceive
himself, ought to build his hypothesis on matter of fact, and make it
out by sensible experience, and not presume on matter of fact, because
of his hypothesis, that is, because he supposes it to be so; which way
of proving amounts to this, that I must necessarily think all last
night, because another supposes I always think, though I myself cannot
perceive that I always do so.

But men in love with their opinions may not only suppose what is in
question, but allege wrong matter of fact. How else could any one
make it an inference of mine, that a thing is not, because we are not
sensible of it in our sleep? I do not say there is no SOUL in a man,
because he is not sensible of it in his sleep; but I do say, he cannot
THINK at any time, waking or sleeping, without being sensible of it. Our
being sensible of it is not necessary to anything but to our thoughts;
and to them it is; and