The mind does not know itself, except insofar as it perceives the ideas of the modifications of the body.

By Baruch Spinoza, from Ethics

Key Arguments

  • The knowledge of the mind follows and is referred to God as does the knowledge of the body (II. xx), but the human mind does not know the human body itself (II. xix.; II. xi. Coroll.), hence thus far has no knowledge of itself.
  • Ideas of bodily modifications involve the nature of the body (II. xvi.) which agrees with the nature of the mind (II. xiii.), so knowledge of these ideas necessarily involves knowledge of the mind; and this knowledge of these ideas is in the mind.

Source Quotes

But the ideas of the modifications of the body are in the human mind (II. xii.), that is, in God, in so far as he constitutes the essence of the human mind; therefore the ideas of these ideas will be in God, in so far as he has the knowledge or idea of the human mind, that is (II. xxi.), they will be in the human mind itself, which therefore perceives not only the modifications of the body, but also the ideas of such modifications. Q.E.D. PROP. XXIII. The mind does not know itself, except in so far as it perceives the ideas of the modifications of the body. Proof.—The idea or knowledge of the mind (II. xx.) follows in God in the same manner, and is referred to God in the same manner, as the idea or knowledge of the body.
II. xi.), the human mind thus far has no knowledge of itself. Further the ideas of the modifications, whereby the body is affected, involve the nature of the human body itself (II. xvi.), that is (II. xiii.), they agree with the nature of the mind; wherefore the knowledge of these ideas necessarily involves knowledge of the mind; but (by the last Prop.) the knowledge of these ideas is in the human mind itself; wherefore the human mind thus far only has knowledge of itself. Q.E.D. PROP. XXIV.

Key Concepts

  • PROP. XXIII. The mind does not know itself, except in so far as it perceives the ideas of the modifications of the body.
  • wherefore the knowledge of these ideas necessarily involves knowledge of the mind; but (by the last Prop.) the knowledge of these ideas is in the human mind itself; wherefore the human mind thus far only has knowledge of itself. Q.E.D.

Context

Ethics II, Prop. XXIII with Proof (lines 1201–1334).