"From the Unconscious to the Conscious 



mysteries ! Dastre characterises as ' unfathomable ' 

 the mystery by which in embryonic development ' the 

 ovum-cell, drawing to itself external material, succeeds 

 in building up the marvellous structure which is the 

 body of an animal, the body of a man, even of a 

 particular man.' Nevertheless explanations have been 

 sought and found. They are disconcertingly feeble. 

 Le Dantec, for instance, declares that the form of a 

 creature, and its whole constitution, necessarily depend 

 on its chemical composition, on the relation established 

 between the specific form and this chemical composition. 

 He writes in all seriousness : ' The form of a greyhound 

 is simply the condition of equilibrium of the greyhound 

 chemical substance/ 



* This,' remarks Dastre * is saying a great deal too 

 much, if it means that the body of the dog is " a 

 substance " which behaves after the fashion of 

 homogeneous isotropical masses like melted sulphur 

 or dissolved salt: it is better, but means much less, 

 if it signifies in the mind of the physiologist that 

 the body of the greyhound is the condition of 

 equilibrium of a heterogeneous, non-isotropic, material 

 system under infinitely numerous chemical and 

 physical conditions. The idea of attributing form 

 and therefore organisation only to chemical com- 

 position, has not had its birth from the mind of 

 chemists, nor from that of physiologists.' 

 In reality the supposed explanation by Le Dantec is 

 nothing but a verbal explanation, which substitutes one 

 difficulty for another. Instead of the question: How 

 is the specific form realised ? we are led, if we admit 

 Le Dantec's hypothesis, to ask: How is the condition 

 of chemical equilibrium which is the basis of the specific 

 form, realised and maintained ? The mystery is just 

 as great as before. But even taken as it stands, the 

 hypothesis cannot be sustained, for it can give 

 no account, as we shall see later on, of the changes 



43 



