thinks. Accordingly, the knowledge, _I_ THINK, THEREFORE _I_ AM, is
the first and most certain that occurs to one who philosophizes
orderly.

VIII. That we hence discover the distinction between the mind and
the body, or between a thinking and corporeal thing.

And this is the best mode of discovering the nature of the mind, and
its distinctness from the body: for examining what we are, while
supposing, as we now do, that there is nothing really existing apart
from our thought, we clearly perceive that neither extension, nor
figure, nor local motion,[Footnote: Instead of "local motion," the
French has "existence in any place."] nor anything similar that can
be attributed to body, pertains to our nature, and nothing save
thought alone; and, consequently, that the notion we have of our
mind precedes that of any corporeal thing, and is more certain,
seeing we still doubt whether there is any body in existence, while
we already perceive that we think.

IX. What thought (COGITATIO) is.

By the word thought, I understand all that which so takes place in
us that we of ourselves are immediately conscious of it; and,
accordingly, not only to understand (INTELLIGERE, ENTENDRE), to will
(VELLE), to imagine (IMAGINARI), but even to perceive (SENTIRE,
SENTIR), are here the same as to think (COGITARE, PENSER). For if I
say, I see, or, I walk, therefore I am; and if I understand by
vision or walking the act of my eyes or of my limbs, which is the
work of the body, the conclusion is not absolutely certain, because,
as is often the case in dreams, I may think that I see or walk,