mind not only precedes, and has greater certainty, but is even
clearer, than that we have of the body, it must be remarked, as a
matter that is highly manifest by the natural light, that to nothing
no affections or qualities belong; and, accordingly, that where we
observe certain affections, there a thing or substance to which
these pertain, is necessarily found. The same light also shows us
that we know a thing or substance more clearly in proportion as we
discover in it a greater number of qualities. Now, it is manifest
that we remark a greater number of qualities in our mind than in any
other thing; for there is no occasion on which we know anything
whatever when we are not at the same time led with much greater
certainty to the knowledge of our own mind. For example, if I judge
that there is an earth because I touch or see it, on the same
ground, and with still greater reason, I must be persuaded that my
mind exists; for it may be, perhaps, that I think I touch the earth
while there is one in existence; but it is not possible that I
should so judge, and my mind which thus judges not exist; and the
same holds good of whatever object is presented to our mind.

XII. How it happens that every one does not come equally to know
this.

Those who have not philosophized in order have had other opinions on
this subject, because they never distinguished with sufficient care
the mind from the body. For, although they had no difficulty in
believing that they themselves existed, and that they had a higher
assurance of this than of any other thing, nevertheless, as they did
not observe that by THEMSELVES, they ought here to understand their
MINDS alone [when the question related to metaphysical certainty];
and since, on the contrary, they rather meant their bodies which