GENERATION OF ANIMALS 



there is nothing more fundamental in Aristotle's — and 

 in his predecessors' — idea of 8wa/i.tj than that it is 

 something natural ; and the associations of the term 

 " force " run counter to this. Aristotle himself con- 

 trasts " natural " and " enforced " movement (see 

 App. B § 22, and cf. 739 a 4, 788 b 27, Politics 1253 b 22). 

 It is also important that any notion of a vague and 

 indefinite urge, even (and perhaps especially) where 

 Soul is involved, should be excluded ; for, as we have- 

 seen, 8uva/iis is associated primarily with some material 

 substance of a specific character or with some Kivrjais 

 (carried in a definite substance) of a specific character. 

 From every point of view it is best to avoid " force " 

 altogether as a translation of Svvafus. 



To vypov Kal to ^i)p6v, "Jiuid substance and solid 

 substance " 



(38) These are two of the original Swdfieis (§ 24) ; and Translation, 

 following Ogle in his translation of P. A. I use the above 

 renderings as being more in conformity with the defini- 

 tions given by Aristotle himself than " moist " and 



" dry " which have sometimes been used. Actually 

 neither pair of English words quite expresses the Greek. 

 Aristotle's definition of them (at G. 4" C. 329 h 30) is Definition, 

 this : " vypov is that which is not bounded by any 

 boundary of its own but can readily be bounded ; ^Tjpov 

 is that which is readily bounded by a boundary of its 

 own but can with difficulty be bounded " ; at the end 

 of each definition there should of course be understood 

 " by a boundary imposed from without." (vypov is to 

 dopiOTov oiKeio) opat evopiarov ov, ^rjpov is to evopiarov fiev 

 olKeiip 6p<x) hvaopiarov he.) 



^i'fifi€Tpia, K/aacris 



(39) An idea which recurs a number of times in G.A. is that Correct pro- 

 of avfifxerpia. In this treatise the majority of the refer- portion : 

 ences " to avp.y.eTpia are concerned with the relative ^"^ ^^ .. 

 amounts of residue contributed in generation by the two *''^° * '°° ' 



« See list of passages in the Index. 



Iv 



