NOTE ON SPACE AND TIME
The imprecision which exists these days with regard to space and time, as much in science as in philosophy, and which has such dangerous consequences for our capacity to think rationally, derives precisely from an inability to distinguish their different natures. For considerations that are entirely practical - establishing the position and the displacements of a body - time, which is to say movement, has been measured by a standard that is, necessarily, static. How could it be otherwise? The unit with which we measure space and the unit with which we measure time are immobile extensions to which the place and movement of a body, each, without distinction, are referred; but this practical consideration shouldn't prevent our good sense from correcting its faults. Above all when we claim to be throwing light on the order of nature.
It is true that positivist philosophy and science have accepted a priori certain limitations - a refusal to consider first causes or last ends. It is even more true that by nature we mean everything around us that might strike the senses, but we pay no attention to the nature of this 'us' which we are keen to pronounce is a negligible quantity, while the absolute quantity is entirely external.
In any case, this confusion of two different quantities isn't something that is unique to our own time. History tells us this clearly - if only through the so-called sophisms of the Eleatics, paradoxes that can easily be resolved by a little bit of experimental reason, operating on the basis of its own mode of operation. Zeno, with his arrow which, immobile in space, nonetheless goes to its target through a series of immobilities, knows perfectly well what the flaw is in his operation; but he also knows what is wrong with the thinking of his age and he poses this sticking point to the intellectuals surrounding him who, already, are inclined to submit their power of reasoning to inert sensations and to the absurdity that follows - a confusion of the natures of space and time which is caused by calculations that can only operate, for both the one and the other, on the basis of units of measurement.
The false reasoning with an appearance of truth proposed by Zeno exposes in advance all the reasonings that derive from these false foundations, not only in Greece but everywhere else and in all the centuries to follow.
As for our own time, we can without hesitation say that the present state of our philosophy and, even more, of our physics, derives from this aberration. And yet nothing is simpler than to put it right. When the arrow is in the bow it is in a place, it is immobile, relatively so but nonetheless immobile in its nature as an arrow. When it will have reached the target it will once again have found a place, once again it will be immobile. That is what is called being in space, in an extension, an inert unit of measurement. Between these two places, when it is flying, it is, while to all appearances remaining an arrow, in reality a period of the impulse received from the movement. It is nowhere, place is suppressed, that is what is called being in time, characterised by cadence, by periods more or less short and more or less numerous as the case may be: sequens, sequentes, sequentia.
If one is unfortunate enough to take arrow, unit of measurement and period for one and the same thing, one has abandoned reason. All the more so if one calls on a perfected mechanical observer which can, basically, do nothing more than register what appears before the senses, that is to say, a body that is perfectly stupid and incapable of establishing any difference between a unit of measurement that is located and a period, which isn't - between that which is a static extension and that which is a process of flowing.
A complaint that can moreover be made against all those instruments of observation that can operate only on the apparent immobility of bodies, whatever might be their size and their appearances as they move. Movement, which essentially belongs to the past and to the future, is closed to them as it is to our senses, concentrated as they are exclusively on the impressions they receive. Yet anyone with a reasoning faculty can, on the basis of their own experience and their ability to reflect on it, conclude that, while never ceasing to be themselves, when they are seated they are not walking and when they are walking they are no longer seated. In other words, when they are seated they are in a place but they cease to be in a place once they are walking, no matter how slowly or how fast. Even if a photographic eye is introduced that will falsify the process of walking, for example stopping it on a raised leg. This misleading image is still not enough to fool the reason so far as to take it as a proof that all movement is made up of a succession of immobile places.
But we still need to explain how and when these immobilities cease to be immobile and are interwoven to become their own opposites in movement. The truth is that space and time are two natures with different characteristics that belong to us, and they cannot coexist since they contradict each other. At least so far as concerns Man, who is their source through his own natural and practical duality. Their absolute simultaneity can only be transcendent. But that is a matter for the theologian, not for the philosopher nor the physicist who, these days, seem to have no notion of it.