Time does not exist without change

Time does not exist without change.

We do not realize that time has elapsed when:

• the state of our own minds does not change at all, or
• we have not noticed its changing

any more than those who are fabled to sleep among the heroes in Sardinia do when they are awakened; for they

People connect the earlier ‘now’ with the later and make them one.

• They cut out the interval because of their failure to notice it.

If the ‘now’ were exactly the same as the past, then there would not have been time.

And so, the nonrealization of the existence of time happens to us when we do not distinguish any change.

• But the soul seems to stay in one indivisible state

When we perceive and distinguish change, we say time has elapsed.

Thus, time dependends on movement and change.

Time is neither movement nor independent of movement.

We must take this as our starting-point if we wish to know what time:

• is
• has to do with movement.

We perceive movement and time together.

Even when it is dark and we are not being affected through the body, if any movement takes place in the mind, we suppose that some time also has elapsed.

When some time is thought to have passed, some movement has taken place along with it.

Hence, time is either movement or something that belongs to movement.

• Since it is not movement, then it must be the other.

But what is moved is moved from something to something, and all magnitude is continuous.

Therefore, the movement goes with the magnitude.

Because the magnitude is continuous, the movement too must be continuous, and if the movement, then the time.

This is because the time that has passed is always thought to be in proportion to the movement.

The distinction of ‘before’ and ‘after’ holds primarily in place, in virtue of relative position.

Since ‘before’ and ‘after’ hold in magnitude, they must hold also in movement, these corresponding to those.

But also in time the distinction of ‘before’ and ‘after’ must hold. This is because time and movement always correspond with each other.

The ‘before’ and ‘after’ in motion is identical in substratum with motion, yet differs from it in definition, and is not identical with motion.

But we apprehend time only when we have marked motion, marking it as ‘before’ and ‘after’.

It is only when we have perceived ‘before’ and ‘after’ in motion that we say that time has elapsed.

We mark them by judging that:

• A and B are different
• some third thing is intermediate to them

When we think that A and B are extremes, different from the middle.

The mind pronounces that the ‘nows’ are two. We then say that there is time, and that this is time.

This is because what is bounded by the ‘now’ is thought to be time (we may assume this).

No time is thought to have elapsed when we perceive the ‘now’ as one, and not as ‘before’ and ‘after’ in a motion.

• This is because there has been no motion either.

On the other hand, when we do perceive a ‘before’ and an ‘after’, then we say that there is time.

• For time is just thisnumber of motion in respect of ‘before’ and ‘after’.

Hence time is not movement, but only movement in so far as it admits of enumeration.

Proof: we discriminate the more or the less by number, but more or less movement by time.

Time then is a kind of number.

Number is used in 2 senses:

1. The countable
2. That with which we count

Time obviously is what is counted, not that with which we count.

Motion is a perpetual succession, so also is time.

But every simultaneous time is self-identical.

This is because the ‘now’ as a subject is an identity, but it accepts different attributes.

The ‘now’ measures time, in so far as time involves the ‘before and after’.

The ‘now’ in one sense is the same, in another it is not the same.

In so far as it is in succession, it is different (which is just what its being was supposed to mean), but its substratum is an identity: for motion, as was said, goes with magnitude, and time, as we maintain, with motion.

Similarly, then, there corresponds to the point the body which is carried along, and by which we are aware of the motion and of the ‘before and after’ involved in it.

This is an identical substratum (whether a point or a stone or something else of the kind), but it has different attributes as the sophists assume that Coriscus’ being in the Lyceum is a different thing from Coriscus’ being in the market-place. And the body which is carried along is different, in so far as it is at one time here and at another there.

But the ‘now’ corresponds to the body that is carried along, as time corresponds to the motion.

For it is by means of the body that is carried along that we become aware of the ‘before and after’ the motion, and if we regard these as countable we get the ‘now’. Hence in these also the ‘now’ as substratum remains the same (for it is what is before and after in movement), but what is predicated of it is different; for it is in so far as the ‘before and after’ is numerable that we get the ‘now’.

This is what is most knowable: for, similarly, motion is known because of that which is moved, locomotion because of that which is carried. what is carried is a real thing, the movement is not.

Thus what is called ‘now’ in one sense is always the same; in another it is not the same: for this is true also of what is carried.

If there were no time, there would be no ‘now’, and vice versa.

The moving body and its locomotion involve each other mutually.

So too do the number of the moving body and the number of its locomotion. For the number of the locomotion is time, while the ‘now’ corresponds to the moving body, and is like the unit of number.

Time, then, also is both made continuous by the ‘now’ and divided at it. For here too there is a correspondence with the locomotion and the moving body.

For the motion or locomotion is made one by the thing which is moved, because it is one-not because it is one in its own nature (for there might be pauses in the movement of such a thing)-but because it is one in definition: for this determines the movement as ‘before’ and ‘after’.

Here, too there is a correspondence with the point; for the point also both connects and terminates the length-it is the beginning of one and the end of another.

But when you take it in this way, using the one point as two, a pause is necessary, if the same point is to be the beginning and the end. The ‘now’ on the other hand, since the body carried is moving, is always different.

Hence time is not number in the sense in which there is ‘number’ of the same point because it is beginning and end.

Rather it is number as the extremities of a line form a number, and not as the parts of the line do so, both for the reason given.

• We can use the middle point as two, so that on that analogy time might stand still.

Further, because obviously the ‘now’ is no part of time nor the section any part of the movement, any more than the points are parts of the line-for it is two lines that are parts of one line.

In so far then as the ‘now’ is a boundary, it is not time, but an attribute of it.

In so far as it numbers, it is number

• This is because boundaries belong only to that which they bound, but number (e.g. 10) is the number of horses, and belongs also elsewhere.

Time is:

• ‘number of movement in respect of the before and after’
• continuous since it is an attribute of what is continuous.