Scholium: The idea that constitutes the nature of the human mind is likewise
shown, when considered solely in itself, not to be clear and distinct, as is also the idea
of the human mind and the ideas of affections of the human body insofar as they are
related only to the human mind, as everyone can easily see.
PROPOSITION 29:The idea of the idea of any affection of the human body does not
involve adequate knowledge of the human mind.
Proof: The idea of an affection of the human body (Pr. 27, II) does not involve
adequate knowledge of the body itself; in other words, it does not adequately express
the nature of the body; that is (Pr. 13, II), it does not adequately agree [convenit] with
the nature of the mind. So (Ax. 6, I) the idea of this idea does not adequately express the
nature of the human mind; i.e., it does not involve an adequate knowledge of it.
Corollary: Hence it follows that whenever the human mind perceives things
after the common order of nature, it does not have an adequate knowledge of itself,
nor of its body, nor of external bodies, but only a confused and fragmentary knowl-
edge. For the mind does not know itself save insofar as it perceives ideas of the
affections of the body (Pr. 23, II). Now it does not perceive its own body (Pr. 19, II)
except through ideas of affections of the body, and also it is only through these affec-
tions that it perceives external bodies (Pr. 26, II). So insofar as it has these ideas, it
has adequate knowledge neither of itself (Pr. 29, II) nor of its own body (Pr. 27, II)
nor of external bodies (Pr. 25, II), but only a fragmentary [mutilatam] and confused
knowledge (Pr. 28, II and Sch.).
Scholium: I say expressly that the mind does not have an adequate knowledge,
but only a confused and fragmentary knowledge, of itself, its own body, and external
bodies whenever it perceives things from the common order of nature, that is, whenever
it is determined externally—namely, by the fortuitous run of circumstance—to regard
this or that, and not when it is determined internally, through its regarding several things
at the same time, to understand their agreement, their differences, and their opposition.
For whenever it is conditioned internally in this or in another way, then it sees things
clearly and distinctly, as I shall later show.
PROPOSITION 30:We can have only a very inadequate knowledge of the duration of
our body.
Proof: The duration of our body does not depend on its essence (Ax. 1, II), nor
again on the absolute nature of God (Pr. 21, I), but (Pr. 28, I) it is determined to exist and
to act by causes which are also determined by other causes to exist and to act in a definite
and determinate way, and these again by other causes, and so ad infinitum. Therefore, the
duration of our body depends on the common order of nature and the structure of the uni-
verse. Now there is in God adequate knowledge of the structure of the universe insofar as
he has ideas of all the things in the universe, and not insofar as he has only the idea of the
human body (Cor. Pr. 9, II). Therefore, knowledge of the duration of our body is very
inadequate in God insofar as he is considered only to constitute the nature of the human
mind. That is (Cor. Pr. 11, II), this knowledge is very inadequate in the human mind.
PROPOSITION 31:We can have only a very inadequate knowledge of the duration of
particular things external to us.
Proof: Each particular thing, just like the human body, must be determined by
another particular thing to exist and to act in a definite and determinate way, and this
latter thing again by another, and so on ad infinitum (Pr. 28, I). Now since we have