123 NATURAL SELECTION AND 



On the other hand, the legislators of ancient 

 Lacedsemon knew (like the Chinese) that, to 

 keep institutions from varying, they must ex- 

 clude foreign influences. Greek political ideal- 

 ists, who dreaded change above everything, 

 feared the very neighbourhood of the sea. 1 

 Here we have the equivalent of the identity of 

 type which is maintained in plants where sexual 

 reproduction is avoided. 



The success of mixed races (provided the 

 mixture be a good one), the advantage which 

 has often come to a country even from conflict, 

 are to a great extent to be explained by the ad- 

 ditional chances of favourable variations which 

 such races possess over those who are living 

 on with the same stock of blood, institutions 

 and ideas. " Protestant variations " at least 

 imply intellectual progress. The absence of 

 dissent and of controversy (which is the con- 

 flict and mingling of different ideas) means 

 intellectual sterility. The Jews have remained 

 the same race more than any other people ; but 

 they form no exception, for they have been 

 dwellers in many lands, and whilst strengthened 

 by the persecutions, they have been enriched by 

 1 Cp. Plato, Laws, 704, 705. 



