Confusion arising from prediction of astronomical phenomena.

What makes the confusion a natural and almost an unavoidable one is that science seems to point to many cases where we do anticipate the future. Do we not determine beforehand the conjunctions of heavenly bodies, solar and lunar eclipses, in short the greater number of astronomical phenomena? Does not, then, the human intellect embrace in the present moment immense intervals of duration still to come? No doubt it does; but an anticipation of this kind has not the slightest resemblance to the anticipation of a voluntary act. Indeed, as we shall see, the reasons which render it possible to foretell an astronomical phenomenon are the very ones which prevent us from determining in advance an act which springs from our free activity. For the future of the material universe, although contemporaneous with the future of a conscious being, has no analogy to it.

Illustration from hypothetical acceleration of physical movements.

In order to put our finger on this vital difference, let us assume for a moment that some mischievous illustration genius, more powerful still than the mischievous genius conjured up by Descartes decreed that all the movements of the universe should go twice as fast. There would be no change in astronomical phenomena, or at any rate in the equations which enable us to foresee them, for in these equations the symbol t does not stand for a duration, but for a relation between two durations, for a certain number of units of time, in short, for a certain number of simultaneities: these simultaneities, these coincidences would still take place in equal number: only the intervals which separate them would have diminished, but these intervals never make their appearance in our calculations. Now these intervals are just duration lived, duration which our consciousness perceives, and our consciousness would soon inform us of a shortening of the day if we had not experienced the usual amount of duration between sunrise and sunset. No doubt it would not measure this shortening, and perhaps it would not even perceive it immediately as a change of quantity; but it would realize in some way or other a decline in the usual storing up of experience, a change in the progress usually accomplished between sunrise and sunset.

Astronomical prophecy such as acceleration.

Now, when an astronomer foretells e.g. a lunar eclipse, he merely exercises in his own way the power which we have ascribed to our mischievous genius. He decrees that time shall go ten times, a hundred times, a thousand times as fast, and he has a right to do so, since all that he thus changes is the nature of the conscious intervals, and since these intervals, by hypothesis, do not enter into the calculations. Therefore, into a psychological duration of a few seconds he may put several years, even several centuries of astronomical time: that is his procedure when he traces in advance the path of a heavenly body or represents it by an equation. What he does is nothing but establishing a series of relations of position between this body and other given bodies, a series of simultaneities and coincidences, a series of numerical relations: as for duration properly so called, it remains outside the calculation and could only be perceived by a consciousness capable of living through the intervals and, in fact, living the intervals themselves, instead of merely perceiving their extremities. Indeed it is even conceivable that this consciousness could live so slow and lazy a life as to take in the whole path of the heavenly body in a single perception, just as we do when we perceive the successive positions of a shooting star as one line of fire. Such a consciousness would find itself really in the same conditions in which the astronomer places himself ideally; it would see in the present what the astronomer perceives in the future. In truth, if the latter foresees a future phenomenon, it is only on condition of making it to a certain extent a present phenomenon, or at least of enormously reducing the interval which separates us from it. In short, the time of which we speak in astronomy is a number, and the nature of the units of this number cannot be specified in our calculations; we may therefore assume them to be as small as we please, provided that the same hypothesis is extended to the whole series of operations, and that the successive relations of position in space are thus preserved. We shall then be present in imagination at the phenomenon we wish to foretell; we shall know exactly at what point in space and after how many units of time this phenomenon takes place; if we then restore to these units their psychical nature, we shall thrust the event again into the future and say that we have foreseen it, when in reality we have seen it.

In dealing with states of consciousness we cannot vary their duration without altering their nature.

But these units of time which make up living duration, and which the astronomer can dispose of as he pleases because they give no handle to science, are just what concern the psychologist, for psychology deals with the intervals themselves and not with their extremities. Certainly pure consciousness does not perceive time as a sum of units of duration: left to itself, it has no means and even no reason to measure time; but a feeling which lasted only half the number of days, for example, would no longer be the same feeling for it; it would lack thousands of impressions which gradually thickened its substance and altered its colour. True, when we give this feeling a certain name, when we treat it as a thing, we believe that we can diminish its duration by half, for example, and also halve the duration of all the rest of our history: it seems that it would still be the same life, only on a reduced scale. But we forget that states of consciousness are processes, and not things; that if we denote them each by a single word, it is for the convenience of language; that they are alive and therefore constantly changing; that, in consequence, it is impossible to cut off a moment from them without making them poorer by the loss of some impression, and thus altering their quality. I quite understand that the orbit of a planet might be perceived all at once or in a very short time, because its successive positions or the results of its movement are the only things that matter, and not the duration of the equal intervals which separate them. But when we have to do with a feeling, it has no precise result except its having been felt; and, to estimate this result adequately, it would be necessary to have gone through all the phases of the feeling itself and to have taken up the same duration. Even if this feeling has finally issued in some definite action, which might be compared to the definite position of a planet in space, the knowledge of this act will hardly enable us to estimate the influence of the feeling on the whole of a life-story, and it is this very influence which we want to know. All foreseeing is in reality seeing, and this seeing takes place when we can reduce as much as we please an interval of future time while preserving the relation of its parts to one another, as happens in the case of astronomical predictions. But what does reducing an interval of time mean, except emptying or impoverishing the conscious states which fill it? And does not the very possibility of seeing an astronomical period in miniature thus imply the impossibility of modifying a psychological series in the same way, since it is only by taking this psychological series as an invariable basis that we shall be able to make an astronomical period vary arbitrarily as regards the unit of duration?

Difference between past and future duration in this respect.

Thus, when we ask whether a future action could have been foreseen, we unwittingly identify that time with which we have to do in the exact sciences, and which is reducible to a number, with real duration, whose so-called quantity is really a quality, and which we cannot curtail by an instant without altering the nature of the facts which fill it. No doubt the identification is made easier by the fact that in a large number of cases we are justified in dealing with real duration as with astronomical time. Thus, when we call to mind the past, i.e. a series of deeds done, we always shorten it, without however distorting the nature of the event which interests us. The reason is that we know it already; for the psychic state, when it reaches the end of the progress which constitutes its very existence, becomes a thing which one can picture to oneself all at once. Here we find ourselves in the same position as the astronomer, when he takes in at a glance the orbit which a planet will need several years to traverse. In fact, astronomical prediction should be compared with the recollection of the past state of consciousness, not with the anticipation of the future one. But when we have to determine a future state of consciousness, however superficial it may be, we can no longer view the antecedents in a static condition as things; we must view them in a dynamic condition as processes, since we are concerned with their influence alone. Now their duration is this very influence. Therefore it will no longer do to shorten future duration in order to picture its parts beforehand; one is bound to live this duration whilst it is unfolding. As far as deep-seated psychic states are concerned, there is no perceptible difference between foreseeing, seeing, and acting.