All the bodies that make up the world around us are emergent. This is because of their being attributed with accidents.
Body: a being with dimensions (a height, width, or depth) stretched out in space. For example: animals.
Accident: a quality that is not intrinsic to the being it is attributed to. Such that if this quality ceases to exist, it is not necessary for this being to cease to exist. For example: motion.
The proof for the emergence of bodies is called Burhan Huduth Al-Ajsam. It can be argued for using the following syllogism:
- Bodies are inseparable from accidents.
- Whatever is inseparable from accidents, is emergent.
- Therefore, bodies are emergent.
The truth of the conclusion will pave the way for proving the existence of God. Since the emergence of bodies is proof for the existence of a creator who brought them into existence.
Premise 1: bodies are inseparable from accidents
The first premise of Burhan Huduth Al-Ajsam proposes that it is impossible for a body to exist without any accidents.
Bodies are inseparable from accidents, because bodies are inseparable from rest and motion. And each of rest and motion is an accident.
Premise 2: whatever is inseparable from accidents, is emergent
The second premise of Burhan Huduth Al-Ajsam proposes that a being inseparable from accidents, is itself emergent.
This premise is true, because the set of all accidents is emergent. So since the being in question is inseparable from accidents, it could not have existed before the set of all accidents emerged into existence. Thus, this being’s existence is preceded by its non-existence (i.e. it is emergent).
The set of all accidents is emergent, because each accident is emergent, and the number of accidents that emerged into existence in the past is finite. Each accident is emergent because they can cease to exist, and whatever can cease to exist has a beginning. The number of accidents that emerged into existence in the past is finite, because Tasalsul is impossible.
Therefore, bodies are emergent
The two premises are true, so the conclusion necessarily follows. Therefore, all bodies are emergent. This means all those bodies that make up the world around us– the stars, the mountains, the trees– began to exist. From there, we can deduce the existence of God.
 Consider the distinction between a body, and the motion of this body. If this motion ceases to exist, it is not necessary that the body cease to exist as well. Motion is therefore, said to be accidental for the body.
 During every moment of a body’s existence, the body is necessarily attributed with either rest or motion. This is true by virtue of what a body is; a being with dimensions stretched out in space. So either this being occupies its space while not having been in a different space during the previous moment in time (and this is called rest), or the body occupies its space while having been in a different space during the previous moment in time (and this is called motion).
 A body, by virtue of what it is, accepts the occupation of a place other than the one that it occupies. This is because no absurdity entails from supposing its existence in a place other than the one it currently exists in.
Thus, any body that is resting in a particular place, can move from the place that it occupies. And any body that has moved from the place that it previously occupied, could have remained in that same place. Entailing the accidentality of both rest and motion.
 If an accident could not cease to exist, then this accident wouldn’t be an accident. As that would make it impossible for the being attributed with it to exist without it.
 In summary: the existence of that which can cease to exist is possible, since such an essence accepts non-existence. Its existence is therefore contingent upon an extrinsic specifier to have brought it into existence. More on this here.
 Tasalsul: the belief that the past is comprised of an infinite number of events. Commonly referred to as an “infinite regression of past events”.
In summary: Tasalsul is impossible because the past is the series of events which leads up to, and then concludes with the present moment. Therefore, to claim that the past consists of an infinite number of events, is to claim that an infinite number of events was concluded. This is impossible because an infinity is endless by virtue of what it is, and so it cannot be concluded. More on this here.