If those blessed ancient philosophers had not already uttered their
views about time, we would only need to add to the idea of eternity
what we have to say of the idea of time, and to set forth our opinion
on the subject, trying to make it correspond with the already expressed
notion of eternity. But we now must examine the most reasonable
opinions that have been advanced about time, and observe how far our
own opinion may conform thereto.
TIME CONSIDERED EITHER AS MOTION; AS SOMETHING MOVABLE; OR SOMETHING OF
MOTION.
To begin with, we may divide the generally accepted opinions about
time into three classes: time as movement, as something movable, or
as some part of movement. It would be too contrary to the notion of
time to try to define it as rest, as being at rest, or as some part of
rest; for time is incompatible with identity (and consequently with
rest, and with what is at rest). Those who consider time as movement,
claim that it is either any kind of movement, or the movement of the
universe. Those who consider it as something movable are thinking of
the sphere of the universe; while those who consider time as some part
of movement consider it either as the interval of movement, or as its
measure, or as some consequence of movement in general, or regular
movement.