Two Difficulties Regarding Time

As long as we do not go outside the domain of consciousness, the notion of time is relatively clear.

We easily distinguish our present sensation from the remembrance of past sensations or the anticipation of future sensations.

When we say that two conscious facts are simultaneous, we mean that they profoundly interpenetrate, so that analysis can not separate them without mutilating them.

For an aggregate of sensations to have become a remembrance capable of classification in time, it must have ceased to be actual. We must have lost the sense of its infinite complexity. Otherwise, it would have remained present.

It must have crystallized around a center of associations of ideas which will be a sort of label. It is only when they thus have lost all life that we can classify our memories in time as a botanist arranges dried flowers in his herbarium.

But these labels can only be finite in number.

Thus, psychologic time should be discontinuous.

Whence comes the feeling that between any two instants there are others?

We arrange our recollections in time, but we know that there remain empty compartments. How could that be, if time were not a form pre-existent in our minds? How could we know there were empty compartments, if these compartments were revealed to us only by their content?

Into this form, we wish to put not only the phenomena of our own consciousness, but those of which other consciousnesses are the theater.

But more, we wish to put there physical facts, these I know not what with which we people space and which no consciousness sees directly. This is necessary because without it science could not exist.

Thus, psychologic time is given to us and creates scientific and physical time. There the two difficulties begin.

Think of 2 consciousnesses, which are like two worlds impenetrable one to the other.

By what right do we strive to put them into the same mold, to measure them by the same standard?

Is it not as if one strove to measure length with a gram or weight with a meter? Why do we speak of measuring?

We know perhaps that some fact is anterior to some other, but not by how much it is anterior.

Therefore, 2 difficulties:

1. Can we transform psychologic time, which is qualitative, into a quantitative time?

• This difficulty have long been noticed and has been settled

2. Can we reduce to one and the same measure facts which transpire in different worlds?

We have not a direct intuition of the equality of 2 intervals of time.

The persons who believe they possess this intuition are dupes of an illusion. What do I mean when I say, from 12 noon to 1 pm, the same time passes as from 2 pm to 3 pm?

The least reflection shows that by itself it has no meaning at all. It will only have the meaning that I give to it, making it arbitrary.

Psychologists could have done without this definition. But physicists and astronomers could not.

To measure time, physicists use the pendulum. They suppose by definition that all the beats of this pendulum are of equal duration.

But this is only a first approximation. The following make the pace of the pendulum vary:

• temperature
• the resistance of the air
• the barometric pressure
• make the pace

If we could escape these sources of error, we should obtain a much closer approximation. But it would still be only an approximation.

New causes, hitherto neglected, electric, magnetic or others, would introduce minute perturbations.

In fact, the best chronometers must be corrected from time to time. The corrections are made by the aid of astronomic observations. Arrangements are made so that the sidereal clock marks the same hour when the same star passes the meridian.

In other words, it is the sidereal day (the duration of the rotation of the earth) which is the constant unit of time.

It is supposed, by a new definition substituted for that based on the beats of the pendulum, that two complete rotations of the earth about its axis have the same duration.

However, the astronomers are still not content with this definition. Many of them think:

• that the tides act as a check on our globe
• that the rotation of the earth is becoming slower and slower.

Thus would be explained the apparent acceleration of the motion of the moon, which would seem to be going more rapidly than theory permits because our watch, which is the earth, is going slow.