PRACTICAL CONSIDERATIONS 305 



if these hybrids be inbred, the progeny are partly susceptible 

 and partly immune, and all those that are immune breed true. 

 If it is thus possible among plants " to get a pure thing out of 

 an impure " — it may be that for domestic animals and for man 

 himself the purification of a tainted stock is not a chimera. 



(7) As to the diffusion of disease by the intermarriage of 

 badly tainted with relatively healthy families, we have this in 

 our own hands, and we need not whine over it. The basis 

 of preferential mating is not unalterable ; in fact, we know that 

 it sways hither and thither from age to age. Possible marriages 

 are every day prohibited or refrained from for the absurdest of 

 reasons ; there is no reason why they should not be prohibited 

 or refrained from for the best of reasons — the welfare of our race. 

 For the average man instinctive " falling in love " will probably 

 remain a safer guide than any scientific eugenic counsels, but 

 there is no reason to doubt that eugenic considerations will in 

 the course of time enter subconsciously into the prolegomena 

 of that mysterious process. Moreover in manv matings there 

 is no question of love at all. 



By the education of conscience on a scientific basis there is 

 already arising a wholesome prejudice against the marriage and 

 especially the intermarriage of subjects in whom there is a 

 strong hereditary bias to certain diseases — such as epilepsy 

 and diabetes, to take two very different instances. Is it Utopian 

 to hope that this will extend with increasing knowledge, and 

 that the ethical consciousness of the average man will come 

 more and more to include in its varied content " a feeling of 

 responsibility for the healthfulness of succeeding generations " ? 

 It seems more direct in the German phrase — " Verantwortungs- 

 gefiihl vor der Heiligkeit der kommenden Generationen." 



The argument always used against deliberate preferential 

 mating on a eugenic basis is that our ignorance is immense. 

 And this must be frankly admitted. Yet there are some things 

 that we do know. We know that " the manifestly syphilitic 



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