PRACTICAL PROBLEMS 339 



is rarely manifested, it is clearly beyond the power of artificial 

 selection to render the race insusceptible to them. The 

 only hope of lessening the evils caused by them lies in the 

 discovery of vaccine lymphs similar to that which has already 

 banished small-pox. 



525. We have seen that just as all races undergo protective 

 evolution against other stringently selective agents of elimin- 

 ation, so various races of mankind have undergone evolution 

 against certain narcotics. Human races that have not under- 

 gone this evolution, to some extent at least, are now as in- 

 capable of existing under the conditions of civilization as 

 races that have undergone no evolution against tuberculosis. 

 On the other hand, some races that have undergone consider- 

 able evolution are now hardly injured by the presence of 

 almost unlimited supplies of alcohol (or other lethal narcotics). 

 Nature, in effect, has carried on a great and successful scheme 

 of temperance reform, but on lines opposite to those advocated 

 by human reformers. She has eliminated drunkards ; temper- 

 ance reformers propose to eliminate drink. 



526. We have seen also that every race which has under- 

 gone any phase of evolution tends to regress, with a rapidity 

 that is proportionate to the rapidity of the previous evolution, 

 towards the ancestral type when the eliminating agency 

 which caused the evolution is withdrawn. It follows, were 

 alcohol or opium withdrawn from a race which has under- 

 gone evolution against it, the race would gradually lose 

 its innate resisting power and revert steadily towards that 

 ancestral type in which the susceptibility to the charm of 

 alcohol was very great. It follows, further, that repressive 

 legislation, unless it were made eternal, would result ultimately 

 in disaster. If passed by a race that had undergone evolution, 

 it would be in danger of repeal by descendants who had 

 undergone reversion. In this instance at least it would not 

 be possible to give immortal permanence to a mortal law. 

 Any one with a basket of fruit is able to manufacture alcohol ; 

 it is used in our arts and sciences, and men will drink ether 

 or methylated spirits when they cannot procure anything 

 more palatable ; l some races, as the South Europeans, have 



1 " An Inflammable Beverage. A Bill has been introduced into the 

 Manx Legislature for regulating the sale of methylated spirits. The 

 measure is prompted by the necessity of preventing the use of this spirit 

 as a beverage, especially among the lower classes during Sundays and 

 hours i^ien the public-houses are closed. It is provided that only 

 licensed persons may sell methylated spirits at places mentioned in the 

 licence. Publicans are prohibited from taking out such a licence, and 

 the sale of methylated spirits by any one is forbidden between Saturday 



