EUGENICS 135 



It is not by a timid conservatism sticking to every jot and tittle of 

 the customs which gifted men of the past have taught the world, that 

 we shall prevent backsliding: it is far safer to trust gifted men of the 

 present and future to keep what is good in our traditions, and to im- 

 prove them. The only safe way to conserve the good wrought by the 

 past is to improve on it. 



It is beyond the province of this lecture to devise biologically helpful 

 and socially innocuous schemes of selective breeding, but I may be per- 

 mitted to record my faith that if mankind to-day really wanted to 

 improve the original nature of its grandchildren as much, say, as it 

 wants to improve the conditions of life for itself and its children, and 

 believed certain facts of biology and psychology as effectively, say, as it 

 believes that wealth gives power or that disease brings misery, appro- 

 priate schemes for selective breeding would be devised well within the 

 span of our own lives. 



Any form of socially innocuous selective breeding will improve the 

 stock by reproducing from those members of it who have shown, by 

 ancestral and personal achievement, with due allowance for favorable 

 or unfavorable circumstances, the superiority of the germ plasm which 

 they bear. But some forms may be far more effective than others 

 according to the way in which the original components of intellect, 

 character, energy, skill, stability and the like in the germs are consti- 

 tuted. Suppose, for example, that the original germinal basis for 

 human intellect consisted in the presence of a certain constant some- 

 thing, call it "In, the determiner for intellect," in the germ or ovum. 

 The fertilized ovum, which is the human life at its beginning, could 

 then have I n double, if both the germ and ovum had it ; I n single if one 

 or the other had it ; or could lack Z„, as it must if neither had it. Sup- 

 pose that the consequences of these three conditions were that the ItJn 

 individuals would tend, with fair conditions in life, to be specially 

 gifted; that the I n individuals would tend to be of "normal" intellect; 

 that the individuals lacking I n would tend to be feeble-minded. It is 

 then the case that of the germs produced by the individual who had I n In 

 at the start of his life, each contains 7„, that of the germs produced by 

 the individual who had I„ at the start of his life, half have I n and half 

 lack it, and that of the germs produced by the individual who lacked I n 

 at the start of his life, no one has 7„. Consequently, by discovering the 

 individuals who lacked I„ at the start of life and preventing them from 

 breeding, we could rapidly reduce feeble-mindedness. By discovering 

 the individuals who had I„I n at the start of life and breeding exclusively 

 from them, we could eradicate feeble-mindedness and ordinariness both, 

 leaving a race of only the specially gifted. The discovery could be made 

 in a few generations of experimental breeding; and the exclusion, of 

 course, could be made one generation after the discovery. 



