174 MENDELISM chap, xv 



measure the arbiters of the destiny of those within 

 whom they dwell. At the moment of union of two 

 gametes is decided the character of another zygote, 

 as well as the nature of the population of gametes 

 which must make its home within him. The union 

 once, effected the inevitable sequence takes its course, 

 and whether it be good, or whether it be evil, we, the 

 zygotes, have no longer power to alter it. We are in 

 the hands of the gamete ; yet not entirely. For 

 though we cannot influence their behaviour we can 

 nevertheless control their unions if we choose to do 

 so. By regulating their marriages, by encouraging 

 the desirable to come together, and by keeping the 

 undesirable apart we could go far towards ridding 

 the world of the squalor and the misery that come 

 through disease and weakness and vice. But before 

 we can be prepared to act, except, perhaps, in the 

 simplest cases, we must learn far more about them. 

 At present we are woefully ignorant of much, though 

 we do know that full knowledge is largely a matter 

 of time and means. One day we shall have it, and 

 the day may be nearer than most suspect. Whether 

 we make use of it will depend in great measure upon 

 whether we are prepared to recognise facts, and to 

 modify or even destroy some of the conventions 

 which we have become accustomed to regard as the 

 foundations of our social life. Whatever be the 

 outcome, there can be little doubt that the future of 

 our civilisation, perhaps even the possibility of a 

 future at all, is wrapped up with the recognition we 

 accord to those who live unseen and inarticulate 

 within us — the fateful race of gametes so irrevocably 

 bound to us by that closest of all ties, heredity. 



