Avicennas Theory of Matter and Corporeity

According to Avicenna, body (Jism) is said of different things. In the sense of natural body Jism tabVl), it denotes the substance in which three dimensions bu d), perpendicular to one another can be postidated. He is, nonetheless, aware that were the dimensions hypothesised to become actual, they would be accidental, rather than essential, features of body for this reason, he considers this definition a description rasm) of body, as opposed to a real definition (hadd), which would only consist of essential features of what is defined. In one place, Avicenna gives the real definition of body as the form of continuity (ittisdl), which receives the positing of the three dimensions we have mentioned . Continuity here is used in the sense of divisibility, which is the absolute sense of the term a thing is continuous in itself if we can postulate divisions within it, such that any two postulated divisions share a common boundary.  

1 See also Shihadeh, Avicenna s Corporeal Form and Proof of Prime Matter. In the present chapter, Sections 6.i and 6.2 and part of Section 6.3 draw closely on this article. 

5 In addition to this absolute sense, Avicenna gives two further, relative definitions for continu-ity , namely contiguity, that is, when two bodies share a common boundary, in the sense that their surfaces are in contact and attachment, that is, when two bodies are attached to one another, either by adhesion or interconnection (Avicenna, Mantlq, II.III.4,116-117 Tabrfyydt, I.III.2,269-271 cf. Stone, Simplicius and Avicenna , 102). 

in the sense of natural body, is a composite of two primary principles, namely prime matter and corporeal form sura jismiyya). These are the two proximate causes to which body owes its subsistence. The most basic difference between these two principles is that the material cause of body is a passive principle and associated with pure potentiality, whereas the formal cause is an active principle and associated with actuality  

If [the cause of a thing] is included in its constitution and is part of its existence, then either it must be the part where, in terms of its existence alone,i2 it is not necessary for it to be actual, but only to be in potency, and is termed matter . Or [the cause must be] the part whose existence is its being in actuahty, namely form.  

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