Neither, however, is time without mutation: for when there is no change in our thoughts, or if there is, but we are ignorant of it, then it does not appear to us that any time has elapsed; as neither did it to those in Sardis who are fabled to have slept with the heroes who they awoke: for they conjoined the prior with the posterior now, and made them to be one, not taking into account the intermediate time, through not having had a sensible perception of it. As, therefore, if there were no other now, but one and the same, there would be no time, thus also when it is concealed from us that there is a different time, then the intermediate time does not appear to exist. If, therefore, it then happens to us that we do not imagine there is time, when we do not distinguish any mutation, but the soul appears to remain in one and an indivisible, but when we sensibly perceive and distinguish mutation, then we say there has been time; if this be the case, it is evident that
time is not without motion and mutation. But since we investigate what time is, let us assume beginning from hence, what it is belonging to motion; for, together with motion, we have also a sensible perception of time: for even in darkness, and when we are passive to nothing through the body, if there is nevertheless a certain motion in the soul, there immediately also appears to have been some time. But when likewise some time appears to have elapsed, together with this, there seems also to have been some motion. So that time is either motion, or something belonging to motion. Since, therefore, it is not motion, it is necessary that it should be something belonging to motion. But since that which is moved, is moved from something to something and since all magnitude is continuous; motion is consequent to maguitude: for because magnitude is continuous, motion also is continuous; and because motion, also time: for as much motion as there was, so much time likewise always appears to have elapsed. But prior and posterior primarily subsist in place; and here indeed in the position of the parts. Since, however, there are prior and posterior in magnitude, it is also necessary that these should be in motion, analogous to the prior and posterior which are there. Moreover, there are also prior and posterior in time, because one of these is always consequent to the other. But the prior and posterior of these do not in reality differ from motion, but only in essence and definition. We likewise know time when we give a boundary to motion, distinguishing prior and posterior; and we then say there has been time when we receive a sensible perception of prior and posterior in motion. But we distinguish them by apprehending these to be another and another, and also by conceiving that there is something between, different from these: for when we understand that the extremes are different from the middle, and the soul says that there are two instants, the one prior, and the other posterior; then we say that this is time: for that which is bounded by instants appears to be time. And let this be admitted. When, therefore, we have a sensible perception of the now, as one, and there is not any thing as prior and posterior in motion, or when we perceive it as the same, and not belonging to a certain prior and posterior, then there does not appear to have been any time, because neither was there any motion. But when we perceive prior and posterior, then we say there is time: for time is this, the number of motion according to prior and posterior. Time, therefore, is not motion, unless so far as motion has number; an indication of which is this, that we judge of the more and the less by number, but of a greater and less motion by time. Time, therefore, is a certain number. Since, however, number is twofold (for we call both that which is numbered and that which is numerable number, and also that by which we number;) time is that which is numbered, and not that by which we number. But that by which we number is different from that which is numbered.
