ARISTOTLE 



phenomenon in the realm of Nature. The whole of 

 Book V is devoted to those features — " conditions " 

 {iTddr]) as Aristotle calls them — in animals which are in 

 no way due to a Yinal Cause but are due purely to 

 Necessity, i.e., to Material and Motive Causes. 

 Necessity : (7) We must, however, distinguish two sorts of Necessity 

 (the second of which will be the one just described) : 

 (i) "con- (1) Thefirstisthat which elsewhere (f.(7.,P.y/. 642 a 7 ff., 



ditional •• ; a 32 flf. ; cf. 639 b 25 if., P/njs. 199 b 33 ff.) 



Aristotle describes as "conditional" (e^ vnoddaews) 

 Necessity ; that is to say, assuming that some end 

 or purpose is to be achieved, certain means are 

 necessary in order to achieve it. In other words, 

 this is the sort of Necessity which is implied by the 

 Final Cause being what it is. Thus, if a piece of 

 wood is to be split, an axe or some such instrument 

 is necessary, and the axe must, owing to the nature 

 of the circumstances, be hard and sharp, hence of 

 necessity bronze or iron must be used to make it. 

 The same sort of Necessity is obviously involved in 

 the construction by Nature of the living body and 

 its various parts : certain materials must of necessity 

 be used and certain processes gone through if this 

 or that living body is to be produced." 

 (ii) "ab- (2) The other sort of Necessity is that which Aristotle 



solute," (Phys. 199 b 33 et al. ) calls " simple " or " absolute " 



Necessity (airXcos). This applies in cases (a) where 

 the presence of a material object or set of objects 

 {i.e., a Material Cause), and the fact that their 

 nature is what it is, entails as a necessary con- 

 sequence a certain result or set of results ; (6) where 

 the nature of the " movement " set up by an activat- 

 ing agent (a Motive Cause) similarly entails certain 

 results. This " simple " or " absolute " Necessity 

 may therefore be regarded as the sort of Necessity 

 involved in the Material and Motive Causes — as a 

 reassertion of themselves by these Causes against 

 the Final Cause {G.A. 778 b 1) and against Nature 

 as she advances towards her achievement of it. 

 " In the field of natural objects. Necessity is what 



o- Thus even this Necessity can be said to be located " in the matter " 

 (Phvs. 200 a 15). 



xlii 



