o many things which the mind wonders at.

Again, no one knows how or by what means the mind moves the
body, nor how many various degrees of motion it can impart to the
body, nor how quickly it can move it. Thus, when men say that
this or that physical action has its origin in the mind, which
latter has dominion over the body, they are using words without
meaning, or are confessing in specious phraseology that they are
ignorant of the cause of the said action, and do not wonder at
it.

But, they will say, whether we know or do not know the means
whereby the mind acts on the body, we have, at any rate,
experience of the fact that unless the human mind is in a fit
state to think, the body remains inert. Moreover, we have
experience, that the mind alone can determine whether we speak or
are silent, and a variety of similar states which, accordingly,
we say depend on the mind's decree. But, as to the first point,
I ask such objectors, whether experience does not also teach,
that if the body be inactive the mind is simultaneously unfitted
for thinking? For when the body is at rest in sleep, the mind
simultaneously is in a state of torpor also, and has no power of
thinking, such as it possesses when the body is awake. Again, I
think everyone's experience will confirm the statement, that the
mind is not at all times equally fit for thinking on a given
subject, but according as the body is more or less fitted for
being stimulated by the image of this or that object, so also is
the mind more or less fitted for contemplating the said object.

But, it will be urged, it is impossible that solely from the
laws of nature considered as extended substance, we should be
able to deduce the causes of buildings, pictures, and things of
that kind, which are produced only by human art; nor would the
human body, unless it were determined and led by the mind, be
capable of building a single temple. However, I have just
pointed out that the objectors cannot fix the limits of the
body's power, or say what can be concluded from a consideration
of its sole nature, whereas they have experience of many things
being accomplished solely by the laws of nature, which they would
never have believed possible except under the direction of mind:
such are the actions performed by somnambulists while asleep, and
wondered at by their performers when awake. I would further call
attention to the mechanism of the human body, which far surpasses
in com