Thus, the extension of the life of the soul produces time, and the perpetual progression of her life produces the perpetuity of time, and her former life constitutes the past. We may therefore properly define time as the life of the soul considered in the movement by which she passes from one actualization to another.
We have already decided that eternity is life characterized by rest, identity, immutability and infinity (in intelligence). It is, further, (admitted that) this our world is the image of the superior World (of intelligence). We have also come to the conclusion that time is the image of eternity. Consequently, corresponding to the Life characteristic of Intelligence, this world must contain another life which bears the same name, and which belongs to that power of the universal Soul. Instead of the movement of Intelligence, we will have the movement characteristic of a part of the soul (as the universal Soul ceaselessly passes from one thought to another). Corresponding to the permanence, identity, and immutability (of Intelligence), we will have the mobility of a principle which ceaselessly passes from one actualization to another. Corresponding to the unity and the absence of all extension, we will have a mere image of unity, an image which exists only by virtue of continuity. Corresponding to an infinity already entirely present, we will have a progression towards infinity which perpetually tends towards what follows. Corresponding to what exists entirely at the same time, we will have what exists by parts, and what will never exist entire at the same time. The soul's existence will have to be ceaseless acquiring of existence; if it is to reveal an image of the complete, universal and infinite existence of the soul; that is the reason its existence is able to represent the intelligible existence.
Time, therefore, is not something external to the soul, any more than eternity is exterior to existence. It is neither a consequence nor a result of it, any more than eternity is a consequence of existence. It appears within the soul, is in her and with her, as eternity is in and with existence.
11. (12). The result of the preceding considerations is that time must be conceived of as the length of the life characteristic of the universal Soul; that her course is composed of changes that are equal, uniform, and insensible, so that that course implies a continuity of action. Now let us for a moment suppose that the power of the Soul should cease to act, and to enjoy the life she at present possesses without interruption or limit, because this life is the activity characteristic of an eternal Soul, an action by which the Soul does not return upon herself, and does not concentrate on herself, though enabling her to beget and produce. Now supposing that the Soul should cease to act, that she should apply her superior part to the intelligible world, and to eternity, and that she should there remain calmly united—what then would remain, unless eternity? For what room for succession would that allow, if all things were immovable in unity? How could she contain priority, posteriority, or more or less duration of time? How could the Soul apply herself to some object other than that which occupies her? Further, one could not then even say that she applied herself to the subject that occupied her; she would have to be separated therefrom in order to apply herself thereto. Neither would the universal Sphere exist, since it does not exist before time, because it exists and moves within time. Besides, even if this Sphere were at rest during the activity of the Soul, we could measure the duration of her rest because this rest is posterior to the rest of eternity. Since time is annihilated so soon as the Soul ceases to act, and concentrates in unity, time must be produced by the beginning of the Soul's motion towards sense-objects, by the Soul's life. Consequently (Plato463) says that time is born with the universe, because the Soul produced time with the universe; for it is this very action of the Soul which has produced this universe. This action constitutes time, and the universe is within time. Plato does indeed call the movements of the stars, time; but evidently only figuratively, as (Plato) subsequently says that the stars were created to indicate the divisions of time, and to permit us to measure it easily.
Indeed, as it was not possible to determine the time itself of the Soul, and to measure within themselves the parts of an invisible and uncognizable duration, especially for men who did not know how to count, the (world) Soul created day and night so that their succession might be the basis of counting as far as two, by the aid of this variety. Plato464 indicates that as the source of the notion of number. Later, observing the space of time which elapses from one dawn to another, we were able to discover an interval of time determined by an uniform movement, so far as we direct our gaze thereupon, and as we use it as a measure by which to measure time. The expression "to measure time" is premeditated, because time, considered in itself, is not a measure. How indeed could time measure, and what would time, while measuring, say? Would time say of anything, "Here is an extension as large as myself?" What indeed could be the nature of the entity that would speak of "myself"? Would it be that according to which quantity is measured? In this case, time would have to be something by itself, to measure without itself being a measure. The movement of the universe is measured according to time, but it is not the nature of time to be the measure of movement; it is such only accidentally; it indicates the quantity of movement, because it is prior to it, and differs from it. On the other hand, in the case of a movement produced within a determinate time, and if a number be added thereto frequently enough, we succeed in reaching the knowledge of how much time has elapsed. It is therefore correct to say that the movement of the revolution operated by the universal Sphere measures time so far as possible, by its quantity indicating the corresponding quantity of time, since it can neither be grasped nor conceived otherwise. Thus what is measured, that is, what is indicated by the revolution of the universal Sphere, is time. It is not begotten, but only indicated by movement.
The measure of movement, therefore, seems to be what is measured by a definite movement, but which is other than this movement. There is a difference, indeed, between that which is measured, and that which measures; but that which is measured is measured only by accident. That would amount to saying that what is measured by a foot-rule is an extension, without defining what extension in itself is. In the same way, because of the inability to define movement more clearly because of its indeterminate nature, we say that movement is that which is measured by space; for, by observation of the space traversed by movement, we can judge of the quantity of the movement.
12. (13). The revolution of the universal Sphere leads us therefore to the recognition of time, within which it occurs. Not only is time that in which (all things "become," that is, grow), but time has to be what it is even before all things, being that within which everything moves, or rests with order and uniformity. This is discovered and manifested to our intelligence, but not produced by regular movement and rest, especially by movement. Better than rest, indeed, does movement lead us to a conception of time, and it is either to appreciate the duration of movement than that of rest. That is what led philosophers to define time as the measure "of" movement, instead of saying, what probably lay within their intention, that time is measured "by" movement. Above all, we must not consider that definition as adequate, adding to it that which the measured entity is in itself, not limiting ourselves to express what applies to it only incidentally. Neither did we ever discern that such was their meaning, and we were unable to understand their teachings as they evidently posited the measure in the measured entity. No doubt that which hindered us from understanding them was that they were addressing their teachings to learned (thinkers), or well prepared listeners, and therefore, in their writings, they failed to explain the nature of time considered in itself, whether it be measure or something measured.
Plato himself, indeed, does say, not that the nature of time is to be a measure or something measured, but that to make it known there is, in the circular movement of the universe, a very short element (the interval of a day), whose object is to demonstrate the smallest portion of time, through which we are enabled to discover the nature and quantity of time. In order to indicate to us its nature ("being"), (Plato438) says that it was born with the heavens, and that it is the mobile image of eternity. Time is mobile because it has no more permanence than the life of the universal Soul, because it passes on and flows away therewith; it is born with the heavens, because it is one and the same life that simultaneously produces the heavens and time. If, granting its possibility, the life of the Soul were reduced to the unity (of the Intelligence), there would be an immediate cessation of time, which exists only in this life, and the heavens, which exist only through this life.
The theory that time is the priority and posteriority of this (earthly) movement, and of this inferior life, is ridiculous in that it would imply on one hand that (the priority and posteriority of this sense-life) are something; and on the other, refusing to recognize as something real a truer movement, which includes both priority and posteriority. It would, indeed, amount to attributing to an inanimate movement the privilege of containing within itself priority with posteriority, that is, time; while refusing it to the movement (of the Soul), whose movement of the universal Sphere is no more than an image. Still it is from the movement (of the Soul) that originally emanated priority and posteriority, because this movement is efficient by itself. By producing all its actualizations it begets succession, and, at the same time that it begets succession, it produces the passing from one actualization to another.
(Some objector might ask) why we reduce the movement of the universe to the movement of the containing Soul, and admit that she is within time, while we exclude from time the (universal) Soul's movement, which subsists within her, and perpetually passes from one actualization to another? The reason is that above the activity of the Soul there exists nothing but eternity, which shares neither her movement nor her extension. Thus the primary movement (of Intelligence) finds its goal in time, begets it, and by its activity informs its duration.
How then is time present everywhere? The life of the Soul is present in all parts of the world, as the life of our soul is present in all parts of our body. It may indeed be objected,465 that time constitutes neither a hypostatic substance, nor a real existence, being, in respect to existence, a deception, just as we usually say that the expressions "He was" and "He will be" are a deception in respect to the divinity; for then He will be and was just as is that, in which, according to his assertion, he is going to be.
To answer these objections, we shall have to follow a different method. Here it suffices to recall what was said above, namely, that by seeing how far a man in motion has advanced, we can ascertain the quantity of the movement; and that, when we discern movement by walking, we simultaneously concede that, before the walking, movement in that man was indicated by a definite quantity, since it caused his body to progress by some particular quantity. As the body was moved during a definite quantity of time, its quantity can be expressed by some particular quantity of movement—for this is the movement that causes it—and to its suitable quantity of time. Then this movement will be applied to the movement of the soul, which, by her uniform action, produces the interval of time.
To what shall the movement of the (universal) Soul be attributed? To whatever we may choose to attribute it. This will always be some indivisible principle, such as primary Motion, which within its duration contains all the others, and is contained by none other;466 for it cannot be contained by anything; it is therefore genuinely primary. The same obtains with the universal Soul.
Is time also within us?467 It is uniformly present in the universal Soul, and in the individual souls that are all united together.468 Time, therefore, is not parcelled out among the souls, any more than eternity is parcelled out among the (Entities in the intelligible world) which, in this respect, are all mutually uniform.