nifies a certain kind of duration.
But duration regards existence rather than life. Therefore the word
"life" ought not to come into the definition of eternity; but rather
the word "existence."

Obj. 3: Further, a whole is what has parts. But this is alien to
eternity which is simple. Therefore it is improperly said to be
"whole."

Obj. 4: Many days cannot occur together, nor can many times exist
all at once. But in eternity, days and times are in the plural, for it
is said, "His going forth is from the beginning, from the days of
eternity" (Micah 5:2); and also it is said, "According to the
revelation of the mystery hidden from eternity" (Rom. 16:25).
Therefore eternity is not omni-simultaneous.

Obj. 5: Further, the whole and the perfect are the same thing.
Supposing, therefore, that it is "whole," it is superfluously
described as "perfect."

Obj. 6: Further, duration does not imply "possession." But eternity
is a kind of duration. Therefore eternity is not possession.

_I answer that,_ As we attain to the knowledge of simple things by way
of compound things, so must we reach to the knowledge of eternity by
means of time, which is nothing but the numbering of movement by
_before_ and _after._ For since succession occurs in every movement,
and one part comes after another, the fact that we reckon before and
after in movement, makes us apprehend time, which is nothing else but
the measure of before and after in movement. Now in a thing bereft of
movement, which is always the same, there is no before or after. As
therefore the idea of time consists in the numbering of before and
after in movement; so likewise in the apprehension of the uniformity
of what is outside of movement, consists the idea of eternity.

Further, those things are said to be measured by time which have a
beginning and an end in time, because in everything which is moved
there is a beginning, and there is an end. But as whatever is wholly
immutable can have no succession, so it has no beginning, and no end.

Thus eternity is known from two sources: first, because what is
eternal is interminable--that is, has no beginning nor end (that is,
no term either way); secondly, because eternity has no succession,
being simultaneously whole.

Reply Obj. 1: Simple things are usually defined by way of negation;
as "a point is that which has no parts." Yet this is not to be taken
as if the negation belonged to their essence, but because our
intellect wh