22 



Problems, Concepts and Their History 



mechanical conception will be entered into 

 further in the section to follow; suffice it to 

 conclude here with a few more words about 

 the metaphysical. Modern science considers 

 respect for it a fault, which in many ways it 

 is. But modern science must remember, as 

 Whitehead reminds us, that all thought is 

 abstract, and that intellectual induction at 

 least presupposes metaphysics. And primary 

 success in dealing with the embryo, because 

 of its complexity, must derive from the in- 

 ductive rather than the deductive process. No 

 scientific progress has ever been made with- 

 out reflection and speculation; and it must 

 be remembered that both imply holding a 

 mirror to nature, and that the surfaces must 

 be held true. 



Woodger ('48), as a matter of fact, in a 

 most interesting theoretical paper, "Obser- 

 vations on the present state of embryology," 

 presented recently at the Second Growth 

 Symposium in England, has concerned him- 

 self with the necessary conditions for imme- 

 diate embryological progress, to conclude 

 that what we need is to concentrate our 

 attention on a few key data in order to de- 

 rive the key hypotheses we require to pro- 

 ceed. There is a fallacy here for embryology. 

 The greatest progressive minds of embryol- 

 ogy have not searched for hypotheses; they 

 have looked at embryos. How they have 

 looked, and how they are looking now, is 

 the burden of the section to follow. 



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