For we are supposing that he has seen only one of them in the evening, not both at the
same time. Therefore, his imagination will waver, and he will imagine, along with a
future evening, now one, now the other; that is, he will regard neither of them as going to
be there for certain, but both of them contingently. This wavering of the imagination
occurs in the same way if the imagination be of things which we regard with relation to
past or present time, and consequently we shall imagine things, as related both to present
and past or future time, as contingent.
Corollary 2: It is in the nature of reason to perceive things in the light of eternity
[sub quadam specie aeternitatis].
Proof: It is in the nature of reason to regard things as necessary, not as contingent
(previous Pr.). Now it perceives this necessity truly (Pr. 41, II); that is, as it is in itself
(Ax. 6, I). But (Pr. 16, I) this necessity is the very necessity of God’s eternal nature.
Therefore, it is in the nature of reason to regard things in this light of eternity.
Furthermore, the basic principles of reason are those notions (Pr. 38, II) which explicate
what is common to all things, and do not explicate (Pr. 37, II) the essence of any partic-
ular thing, and therefore must be conceived without any relation to time, but in the light
of eternity.
PROPOSITION 45:Every idea of any body or particular thing existing in actuality
necessarily involves the eternal and infinite essence of God.
Proof: The idea of a particular thing actually existing necessarily involves both
the essence and the existence of the thing (Cor. Pr. 8, II). But particular things cannot be
conceived without God (Pr. 15, I). Now since they have God for their cause (Pr. 6, II)
insofar as he is considered under that attribute of which the things themselves are
modes, their ideas (Ax. 4, I) must necessarily involve the conception of their attribute;
that is (Def. 6, I), the eternal and infinite essence of God.
Scholium: Here by existence I do not mean duration, that is, existence insofar as it
is considered in the abstract as a kind of quantity. I am speaking of the very nature of
existence, which is attributed to particular things because they follow in infinite numbers
in infinite ways from the eternal necessity of God’s nature (Pr. 16, I). I am speaking,
I repeat, of the very existence of particular things insofar as they are in God. For although
each particular thing is determined by another particular thing to exist in a certain man-
ner, the force by which each perseveres in existing follows from the eternal necessity of
God’s nature. See Cor. Pr. 24, I.
PROPOSITION 46:The knowledge of the eternal and infinite essence of God which
each idea involves is adequate and perfect.
Proof: The proof of the preceding proposition is universally valid, and whether a
thing be considered as a part or a whole, its idea, whether of whole or part, involves the
eternal and infinite essence of God (preceding Pr.). Therefore, that which gives knowledge
of the eternal and infinite essence of God is common to all things, and equally in the part
as in the whole. And so this knowledge will be adequate (Pr. 38, II).
PROPOSITION 47:The human mind has an adequate knowledge of the eternal and
infinite essence of God.
Proof: The human mind has ideas (Pr. 22, II) from which (Pr. 23, II) it perceives
itself, its own body (Pr. 19, II), and external bodies (Cor. 1, Pr. 16 and Pr. 17, II) as actu-
ally existing, and so it has an adequate knowledge of the eternal and infinite essence of
God (Prs. 45 and 46, II).