Proposition 31

210. Between a thing whose substance and act are in a moment of eternity and a thing whose substance and action are in a moment of time 'now' there exists an intermediary, and it is that whose substance is in the eternal 'now' and whose act is in the temporal 'now'.

211. This is because a thing whose substance falls under time, i.e., because time contains it, is falling under time in all its dispositions, because of which its action also falls under time; since, insofar as the thing's substance falls under time. But a thing falling under time in all its dispositions is separated from a thing falling under eternity in all its dispositions. But there is continuity only in similar things. Therefore it is necessary that there be some other third thing intermediate between each, whose substance falls under eternity and whose action falls under time.

212. For it is impossible that there be a thing whose substance falls under time and whose action under eternity; indeed, in this way its operation would be better than its substance; but this is impossible.

213. Therefore it is manifest that between things falling under time with respect to their substances and their operations and things whose substances and operations are falling under the limit of eternity there are things falling under eternity with respect to their substances and falling under time with respect to their operations, as we have shown.

451. In the preceding proposition, the order of temporal things to one another was made manifest; here (210) the order of eternal things to one another is made manifest.

And first, it is posited between eternal things, something which is eternal in every way and something which is eternal in a certain way and temporal in a certain way;

second, the circumstances of that which is in some way eternal and in some way temporal is made manifest, in proposition 32, at: every substance (214).

452. About the first, a proposition like this is posited: between a thing whose substance and act are in a moment of eternity and a thing whose substance and action are in a moment of time 'now' there exists an intermediary, and it is that whose substance is in the eternal 'now' and whose act is in the temporal 'now' (210). And is seems here that moment of eternity or time are taken as a measurement, so that, to be precise, that which is measured by eternity is said to be in a moment of eternity and that which is measured in time is said to be in a moment of time.

453. This proposition is also posited as 106 in Proclus' book, under these words: of each one which is in every way eternal according to substance and operation and of each one which has a substance in time, the intermediary is that which is in some way eternal, but in another way is measured by time.

454. Now it might seem to someone that this medium be the celestial body, which indeed is incorruptible according to its substance, but its motion is measured by time. But this is not well said: for in the preceding proposition, that which is always moved was posited simply between temporal things (204). For as Aristotle said in Physics, IV: just as time measures motion, so now the mobile is the measure of time. Whence the celestial body which is moved is not in a moment of eternity but in a moment of time.

455. And besides, motion is not an action of that which is moved, but rather a passion; but it is the action of the mover as is said in Physics, 3; now, the principle of motion is the soul, as is held in the third proposition (30 [86]). Therefore, because the soul is immobile in itself, but its action is motion, consequently the soul is in a moment of eternity according to its substance, but its act is in time; but of the body which is moved, both substance and operation is in time; and the intelligence's substance and action, in a moment of eternity.

456. Now, the proof of this proposition (211) is similar to the proof of the proposition put before: for above (204) it was said that the grades of beings are continuous with one another according to a certain similitude, whence those which are totally dissimilar follow one another in the order of things through something intermediary which has a similitude with each extreme. Now that thing whose substance and action is in time, is totally dissimilar to that whose substance and action is in eternity. Therefore it is necessary that between these there be a third intermediary thing either so that its substance falls under eternity and its action under time or vice-versa.

457. But this cannot be (212) that the substance of any thing be in time and its action in eternity: because thus action would be higher and better than substance, and effect higher and better than cause, which is impossible. Therefore it remains that that intermediary thing be according to substance in a moment of eternity and according to operation in time. And this is what we set out to prove (213).