On the other hand...

On the other hand, all of them accepted the theory of the ninefold celestial spheres as axiomatic, and they related the appearance of time to the circular rotation of the highest firmament. This point is also presented in some places by Ṣadr al-Muta’allihīn.

Regarding these principles and points, questions may be raised about the famous definitions of time, among the most important of which are the following: There is no doubt that time is extended and divisible, and hence is considered to be a kind of quantity or to possess a kind of quantity, but why should it be considered as a quantity of motion?

The simple answer which is given to this question is that time is flowing and not fixed, such that not even two moments of it coexist, and necessarily one part of it must pass before the following part may come into existence. This sort of quantity can only be related to something which is inherently flowing and not fixed, and that would be nothing other than motion.

As was indicated, this answer depends on the fact that gradualness, flux and instability are particular to motion, a motion which is presumed to be specified to the four categories of accidents, and for this reason they deny the possibility that time could be a quantity for corporeal substance. But is this doctrine correct? If it is supposed that there were no accidental motion in the world, would there then be no room for the concept of motion?

Motion is an intermediary between bodies and time, but what kind of intermediary is it? Is it a fixed intermediary ( wāsiṭah dar thubūt ),1 from which it could be concluded that bodies themselves really possess time by means of motion, or is it an accidental intermediary ( wāsiṭah dar ‘urūḍ ), such that bodies themselves never really possess time? In other words, is the attribution of corporeal substance to time an accidental characterization ( ittiṣāf bil-‘araḍ )?

Perhaps the answer which must be given on the basis of the principles [of the mentioned philosophers] to this question is to accept the second alternative. But is it correct to accept that bodies themselves do not possess time, regardless of their continuous and gradual changes? If we suppose that all changes are instantaneous but successive, will there be no precedence and posteriority among them?

Let us assume that they consider motion to be a fixed intermediary and that the true attribution of possessing time by bodies is considered to be posterior to the occurrence of motion.