Propositions 11-13

Proposition 11: The first element, which constitutes the actual being of the human mind, is the idea of some particular thing actually existing.

Proof: The essence of man (by the Coroll. of the last Prop.) is constituted by certain modes of God’s attributes, namely (by 2. Ax. 2), by the modes of thinking, of all which (by 2. Ax. 3) the idea is prior in nature.

When the idea is given, the other modes (namely, those of which the idea is prior in nature) must be in the same individual (by the same Axiom).

Therefore, an idea is the first element constituting the human mind.

But not the idea of a non—existent thing, for then (2.8. Coroll.) the idea itself cannot be said to exist.

It must therefore be the idea of something actually existing. But not of an infinite thing.

For an infinite thing (1.21, 1.22), must always necessarily exist.

This would (by 2. Ax. 1) involve an absurdity.

Therefore, the first element, which constitutes the actual being of the human mind, is the idea of something actually existing. Q.E.D.

Corollary: It follows that the human mind is part of the infinite intellect of God.

Thus when we say, that the human mind perceives this or that, we assert that God has this or that idea, not as he is infinite, but as he is displayed through the human mind’s nature, or as he constitutes the human mind’s essence.

When we say that God has this or that idea, not only as he constitutes the human mind’s essence, but also as he, simultaneously with the human mind, has the further idea of another thing, we assert that the human mind perceives a thing in part or inadequately.ote.

Here, readers will come to a stand.

They will call to mind many things which will cause them to hesitate.

I therefore beg them to accompany me slowly, step by step, and not to pronounce on my statements, until they have read to the end.

Proposition 12. Whatsoever comes to pass in the object of the idea, which constitutes the human mind, must be perceived by the human mind

If the object of the idea perceived by the mind is a body, then everything that happens to that body is perceived by the mind.

Proof: Whatsoever comes to pass in the object of any idea, the knowledge thereof is necessarily in God (2.9 Coroll.), in so far as he is considered as affected by the idea of the said object, that is (2.11), in so far as he constitutes the mind of anything.

Therefore, whatever happens in the object of the idea of the human mind, its knowledge is necessarily in God, since he makes up the human mind’s essence.

Proposition 13: The object of the idea of the human mind is a body – a certain mode of extension which actually exists, and nothing else.

Proof: If the body were not the object of the human mind, the ideas of the modifications of the body would not be in God (2.9. Coroll.) in virtue of his constituting our mind, but in virtue of his constituting the mind of something else.

That is (2.11. Coroll.) the ideas of the modifications of the body would not be in our mind. But (by 2. Ax. 4) we do possess the idea of the modifications of the body.

Therefore the object of the idea constituting the human mind is the body, and the body as it actually exists (2.11).

Further, if there were any other object of the idea constituting the mind besides body, then, as nothing can exist from which some effect does not follow (1.36) there would necessarily have to be in our mind an idea, which would be the effect of that other object (2.11).

But (1. Ax. 5) there is no such idea.

Wherefore the object of our mind is the body as it exists, and nothing else. Q.E.D.

Note: We thus comprehend, not only that the human mind is united to the body, but also the nature of the union between mind and body.

However, no one will be able to grasp this unless he first knows the nature of our body.

Our propositions so far have been entirely general, They apply to animated things.

For of everything there is necessarily an idea in God, of which God is the cause, in the same way as there is an idea of the human body.

Thus whatever we have asserted of the idea of the human body is also asserted of the idea of everything else.

But ideas, like objects, differ from each other.

One is more excellent than another and contains more reality, just as the object of one idea is more excellent than the object of another idea, and contains more reality.