reflection on the operations of our own minds, and be copied from any
internal impression. It may be said, that we are every moment conscious
of internal power; while we feel, that, by the simple command of our
will, we can move the organs of our body, or direct the faculties of our
mind. An act of volition produces motion in our limbs, or raises a new
idea in our imagination. This influence of the will we know by
consciousness. Hence we acquire the idea of power or energy; and are
certain, that we ourselves and all other intelligent beings are
possessed of power. This idea, then, is an idea of reflection, since it
arises from reflecting on the operations of our own mind, and on the
command which is exercised by will, both over the organs of the body and
faculties of the soul.

52. We shall proceed to examine this pretension; and first with regard
to the influence of volition over the organs of the body. This
influence, we may observe, is a fact, which, like all other natural
events, can be known only by experience, and can never be foreseen from
any apparent energy or power in the cause, which connects it with the
effect, and renders the one an infallible consequence of the other. The
motion of our body follows upon the command of our will. Of this we are
every moment conscious. But the means, by which this is effected; the
energy, by which the will performs so extraordinary an operation; of
this we are so far from being immediately conscious, that it must for
ever escape our most diligent enquiry.

For _first_; is there any principle in all nature more mysterious than
the union of soul with body; by which a supposed spiritual substance
acquires such an influence over a material one, that the most refined
thought is able to actuate the grossest matter? Were we empowered, by a
secret wish, to remove mountains, or control the planets in their orbit;