20 THE THEORY OF [pt. 



If, then, Bacon and his successors were right in banishing the 

 concept of teleology from scientific thought, the physico-chemical 

 embryologist need not be alarmed by the finalism with which, 

 according to Rignano, the whole of ontogenetic development is suf- 

 fused. In fact, it is not the phenomenon, but only one way of looking 

 at it, that is finalistic, and it is this aspect of it that must be neglected 

 in scientific work if the gravest confusion is to be avoided. Is there 

 need for the biologist to be any more afraid of the Drieschian en- 

 telechy (Aristotle's eVreXe^em Actuality) making what might be into 

 what is and directing from within the development of the embryo in 

 the egg or the uterus? The word "entelechy" as used by Aristotle 

 meant that which exists in the highest sense of the word, whether 

 actually or potentially, e.g. the sword in the mind of the swordmaker 

 before a single one of the necessary operations of manufacture had 

 been begun. The entelechy therefore operated on the process in 

 question by means of the final cause, and did not reside in the 

 changing entity if it was dead like the sword, though it did if it was 

 alive like the embryo. Driesch frequently says that he uses the word 

 in a quite different sense from Aristotle, but the majority of his 

 readers find it impossible to discover any essential point of divergence. 

 He does at any rate make it much more precise than Aristotle, for he 

 defines it as a non-spatial element in the living being, which at one 

 time suspends possible action and at another time relaxes such 

 suspension, acting in this way as the bearer of "individualising 

 causality" and bringing the animal from potentiality into actuality. 



It seems that this inherent immanent formative power has been 

 translated by biologists of every period since Aristotle into the lan- 

 guage of their time. Just as Driesch now tries to acclimatise it to the 

 unfavourable environment of a post-Cartesian world, so St Gregory of 

 Nyssa, who lived about a.d. 370, clothed it in patristic terminology, 

 and produced a theological variety of neo-vitalism. His most im- 

 portant biological works, the irepl KaraaKevrjq dvdpcoirov, On the making 

 of Man, and Trepl '^v^V'^i On the Soul, contained such passages as these, 

 "The thing so implanted by the male in the female is fashioned 

 into the different varieties of limbs and interior organs, not by the 

 importation of any other power from without, but by the power 

 which resides in it transforming it". And elsewhere, "For just as a 

 man when perfectly developed has a soul of a specific nature, so at 

 the fount and origin of his life, he shows in himself that conformation 



