in that consciousness in its simplest and
most elementary form we may find the true beginning of knowledge. The
method of doubt is at the same time a method of abstraction, by which
Descartes rises above the thought of the particular objects of
knowledge, in order that he may find the primary truth in which lies the
very definition of knowledge, of the reason why anything can be said to
be true. First disappears the whole mass of dogmas and opinions as to
God and man which are confessedly received on mere authority. Then the
supposed evidence of sense is rejected, for external reality is not
immediately given in sensation. It is acknowledged by all that the
senses often mislead us as to the nature of things without us, and
perhaps they may also mislead us as to there being anything without us
at all. Nay, by an effort, we can even carry doubt beyond this point; we
can doubt even mathematical truth. When, indeed, we have our thoughts
directed to the geometrical demonstration, when the steps of the process
are immediately before our minds, we cannot but assent to the
proposition that the angles of a triangle are equal to two right angles;
but when we forget or turn away our thoughts from such demonstration, we
can imagine that God or some powerful spirit is playing upon our minds
to deceive them, also that even our most certain judgments may be
illusory. In this naive manner does Descartes express the idea that
there are necessities of thought prior to, and presupposed in the truth
of geometry. He is seeking to strip thought of all the "lendings" that
seem to come to it from anything but itself, of all relation to being
that can be supposed to be given to it from without, that he may
discover the primary unity of thought and being on which all knowledge
depends. And this he finds in pure self-consciousness. Whatever I
abstract from, I cannot abstract from self, from the "I think" that, as
Kant puts it, accompanies all our ideas; for it was in fact the very
independence of this universal element on the particulars that made all
our previous abstraction possible. Even doubt rests on certitude; alone
with self I cannot get rid of this self. By an effort of thought I
separate my thinking self from all that I think, but the thinking self
remains, and in thinking I am. _Cogito, ergo sum_: "I think, therefore I
am." The objective judgment of self-consciousness is bound up with or
involved in the very faculty of judging, and theref