2O2 Heredity. 



totally diverse, since the very object is to find resemblances and 

 to eliminate differences. All scattered facts, all diversities which 

 cannot be grouped together, are called anomalies, or facts without 

 laws. We may, therefore, speak of facts of spontaneity ; but a law 

 of spontaneity is a contradiction in terms. Where, ex hypothesi, 

 there are no two facts which resemble each other, we may in 

 strictness admit the arbitrary intervention of a creative power, 

 but in no degree the regular and constant action of a law. 



It is therefore impossible to recognize two antagonistic laws, the 

 one heredity, the other spontaneity. And we may add that 

 theories of our own day concerning the origin of species and their 

 evolution, do not admit of anything like a law of spontaneity. 

 Besides selection and heredity, which are the chief factors in this 

 transformation, they do, indeed, presuppose what Wallace calls ' the 

 tendency of varieties to depart indefinitely from the original type;' 

 but this tendency, which is the prime source of all variation, is 

 owing to the action of surrounding conditions that is to say, of 

 accidental and fortuitous causes but by no means to an unintelli- 

 gible entity such as the hypothetical law of P. Lucas. 



III. 



If, then, there is no law of spontaneity, we have only to recognize 

 in the foregoing facts exceptions to the law of heredity. We can 

 only explain these by attributing them, not to a single cause, but to 

 causes. No doubt it is far simpler to say, whenever heredity is at 

 fault, This is the result of spontaneity; spontaneity causes the 

 sudden appearance of such a great man of such a great criminal 

 in a given family; but the simplicity of the explanation is of little 

 account, if it is imaginary. In truth, there is no problem more 

 difficult and more complex than that of accounting for these 

 exceptions, and of pointing out how heredity may be so trans- 

 formed as to become unrecognizable. In the present state of 

 physiology and psychology it is impossible to explain these excep- 

 tional cases in a complete and satisfactory manner. We get but 

 an indistinct view of the explanation. 



The doctrine which regards heredity as the absolute rule, beyond 

 which are only anomalies, is very ancient Aristotle taught it in 

 its strictest form. ' He who does not resemble his parents,' says 



