Philosophic Classics From Plato to Derrida
286 AUGUSTINE
- I want to know the essence and nature of time, whereby we measure the
movement of bodies and say, for instance, that one movement lasts twice as long as
another. Now I have a question to ask. Taking the word “day” to apply not only to the
period of sunlight on earth—day as opposed to night, that is—but to the sun’s whole
course from the east and back to the east again, in the sense that we say, “So many days
elapsed,” meaning to include the nights, and not reckoning the nights as extra time over
and above the days; taking it, then, that the movement of the sun in its circular course
from the east back to the east completes a day, this is my question: is it the movement
itself that constitutes a day? Or the time it takes? Or both? If the movement constitutes
a day, then it would still be one day if the sun were to achieve its circuit in an interval of
time equivalent to a single hour. If it is the time it takes, there would not be a day if the
space between one sunrise and the next were as short as an hour; the sun would have to
go round twenty-four times to make up a day. If both were required complete circuit of
the sun and the customary duration of this—we could not call it a day if the sun traveled
through its whole circuit in the space of an hour, nor could we if the sun stopped and as
much time elapsed as it usually takes to run its whole course from morning to morning.
My question now is not, therefore, what is it that we call a day, but what is time
itself, the time whereby we would be able to measure the sun’s revolution and say that
it had been completed in only half the usual time, if the circuit had occupied only
that space of time represented by twelve hours? We could compare the two periods in
terms of time and say that one was twice the length of the other, and this would still be
possible even if the sun sometimes took the single period, and sometimes the double,
to circle from the east and back to the east again. Let no one tell me, then, that time is
simply the motion of the heavenly bodies. After all, at the prayer of a certain man the
sun halted so that he could press home the battle to victory. The sun stood still, but time
flowed on its way, and that fight had all the time it needed to be carried through to
the finish.
I see, therefore, that time is a kind of strain or tension. But do I really see it? Or
only seem to see? You will show me, O Light, O Truth.
24, 31. Are you commanding me to agree with someone who says that time is the
motion of a body? You do not so command me. No corporeal object moves except
within time: this is what I hear; this is what you tell me. But that a corporeal object’s
movement is itself time I do not hear; this you do not say. When a body moves, I mea-
sure in terms of time how long it is in motion, from the moment when it begins until its
motion ceases. If I did not notice when it began, and it continues to move without my
seeing when it stops, I cannot measure the time, except perhaps the interval between the
moment when I began to watch and that when I ceased to observe it. If my observation
is prolonged, I can only say that the process went on for a long time; I cannot say
exactly how long, because when we add a definite indication of a length of time we do
so by reference to some agreed standard. “This is as long as that,” we say; or “This is
twice as long as that other,” or something similar. If, on the other hand, we have been
able to note the position of some corporeal object when it moves (or when parts of it
move, if, for example, it is being turned on a lathe), and we have observed its starting-
point and its point of arrival, then we are able to state how much time has elapsed while
the movement of the object was effected from the one place to the other, or how long it
has taken to revolve on its axis.
Therefore if the motion of an object is one thing, and the standard by which we
measure its duration another, is it not obvious which of the two has the stronger claim
to be called time? Moreover, if the motion is irregular, so that the object is sometimes
