t will regard both as present to
itself, unless there arise causes which exclude their existence
and presence. Further, no one doubts that we imagine time, from
the fact that we imagine bodies to be moved some more slowly than
others, some more quickly, some at equal speed. Thus, let us
suppose that a child yesterday saw Peter for the first time in
the morning, Paul at noon, and Simon in the evening; then, that
today he again sees Peter in the morning. It is evident, from
II. Prop. xviii., that, as soon as he sees the morning light, he
will imagine that the sun will traverse the same parts of the
sky, as it did when he saw it on the preceding day; in other
words, he will imagine a complete day, and, together with his
imagination of the morning, he will imagine Peter; with noon, he
will imagine Paul; and with evening, he will imagine Simon--that
is, he will imagine the existence of Paul and Simon in relation
to a future time; on the other hand, if he sees Simon in the
evening, he will refer Peter and Paul to a past time, by
imagining them simultaneously with the imagination of a past
time. If it should at any time happen, that on some other
evening the child should see James instead of Simon, he will, on
the following morning, associate with his imagination of evening
sometimes Simon, sometimes James, not both together: for the
child is supposed to have seen, at evening, one or other of them,
not both together. His imagination will therefore waver; and,
with the imagination of future evenings, he will associate first
one, then the other--that is, he will imagine them in the future,
neither of them as certain, but both as contingent. This
wavering of the imagination will be the same, if the imagination
be concerned with things which we thus contemplate, standing in
relation to time past or time present: consequently, we may
imagine things as contingent, whether they be referred to time
present, past, or future.

Corollary II.--It is in the nature of reason to perceive
things under a certain form of eternity (sub quadam aeternitatis
specie).

Proof.--It is in the nature of reason to regard things, not as
contingent, but as necessary (II. xliv.). Reason perceives this
necessity of things (II. xli.) truly--that is (I. Ax. vi.), as it
is in itself. But (I. xvi.) this necessity of things is the very
necessity of the eternal nature of God; therefore, it is in the
nature of reason to regard things under this form of