Between physics and metaphysics: Mulla Sadra on nature and motion

Islam & Science, June, 2003 by Ibrahim Kalin

How Things are Set in Motion

There are two possible ways for a mover to set things in motion: It moves things either 1) directly and by itself or 21 indirectly and by means of something else. A carpenter with his adz is an example for the second type of motion. The immediate act of the mover gives the concept of motion as an accidental property. The act of the mover by means of something else yields the notion of the moving body itself. The mover sets an object in motion without being in need of an intermediary agent like the attraction of the lover by the beloved or the motion of the one who has zeal and desire to learn by the learned one. The first mover, which itself does not move, either grants the moving body the immediate cause by which it moves, or attracts it to itself as its final goal. Everything in the physical world brings about a certain effect not by accident or coincidence but through an extraneous power added to it from outside. And this 'added quality' is either the nature it has or the voluntary power it possesses. In both cases, this power should be related to the thing itself viz., it cannot be totally 'relationless' in respect to it. If this were a kind of motion brought about by the abstract or 'detached' agent (al-mufariq) in a universal manner, this would amount to something other than what is meant by motion in the usual sense of the word. Therefore, the Prime Mover needs and, in fact, employs in things an 'agent' by means of which it sets them in motion. This agent in all contingent beings is 'nature' (tabi'ah). (23)

The next problem Sadra addresses is how the Prime Mover, which itself does not move, is related to contingent beings and material bodies. We may summarize Sadra's argument as follows: A thing's being capable of receiving the effect of motion from the 'detached' agent (al-mufariq) can be attributed to three reasons: the thing itself, some special quality in that thing, or a quality in the detached agent. The first is impossible because, as shown previously, this would lead us to accepting motion-by-itself as a universal and intrinsic quality of thing-ness. Sadra briefly states that the second option i.e., motion through a property or ability in things is the right view. The third option has some points to consider. The actualization of motion through an aspect of the detached agent takes place when the detached agent originates an effect in the thing it sets in motion. This, in turn, may happen either through the will of the detached agent by manipulating something in the thing or through effecting it haphazardly according to its wish.

The last option is not tenable because it terminates the idea of order in nature. Chances or accidental coincidences (al-ittifaqiyyat), says Sadra, are not constant and continuous in nature:

   Chances, as you will learn, are neither constant nor
   dominant (in nature) whereas order in nature is both
   dominant and continuous. There is nothing in nature
   that happens by chance or haphazardly. As you will
   learn, everything in nature is directed towards a
   universal purpose (aghrad kulliyah). Thus, the effect of
   motion cannot be brought about by chance. What
   remains, therefore, (as a valid option) is a particular
   quality in the physical bodies (that move). This
   essential quality (al-khassiyyah) is the source of motion,
   and this is nothing but potency (al-quwwah) and nature,
   by virtue of which things yearn, through motion, for
   their second perfection. (24)