! then," some one will perhaps exclaim, "after all, the
whole question about perception resolves it into a _mere gymnastic_ of
the mind." Good sir--do you know what you are saying? Do _you_ think
that the mind itself is any thing except a mere gymnastic of the mind.
If you do--you are most deplorably mistaken. Most assuredly the mind
only _is_ what the mind _does_. The existence of thought is the exercise
of thought. Now if this be true, there is the strongest possible reason
for treating the problem after a purely speculative fashion. The problem
and its desired solution--these are only the means which enable a new
species of thinking, (and that the very highest) viz. speculative
thinking, to deploy into existence. This deployment is the end. But how
can this end be attained if we check the speculative evolution in its
first movements, by throwing ourselves into the arms of the _apparently_
Common Sense convictions of Dr Reid? We use the word "apparently,"
because, in reference to this problem, the apparently Common Sense
convictions of Dr Reid, are not the _really_ Common Sense convictions of
mankind. These latter can only be got at through the severest discipline
of speculation.

Our final answer, then, to the question which led us into this
digression is this:--It is quite true that the material world exists: it
is quite true that we believe in this existence, and always act in
conformity with our faith. Whole books may be written in confirmation of
these truths. They may be published and paraded in a manner which
apparently settles the entire problem of perception. And yet this is not
the right way to go to work. It settles nothing but what all men, women,
and children have already settled. The truths thus formally
substantiated were produced without an effort--every one has already got
from Nature at least as much of them as he cares to have; and therefore,
whatever their importance may be, they cannot, with any sort of
propriety, be made the subjects of conveyance from man to man. We must
either leave the problem altogether alone, (a thing, however, which we
should have thought of sooner,) or we must adopt the speculative
treatment. The argument, moreover, contained in the preceding paragraph,
appears to render this treatment imperative; and accordingly we now
return to it, after our somewhat lengthened digression.

We must take up the thread of our discourse at the point where we
dropped it. The crisis to which