CIVILIZED NATIONS. 159 



unmarried men, which seems to be a general law, "is 

 mainly due to the constant elimination of imperfect types, 

 and to the skillful selection of the finest individuals out of 

 each successive generation;" the selection relating only to 

 the marriage state, and acting on all corporeal, intellectual, 

 and moral qualities.* We may. therefore, infer that sound 

 and good men who out of prudence remain for a time 

 unmarried do not suffer a high rate of mortality. 



If the various checks specified in the two last paragraphs, 

 and perhaps others as yet unknown, do not prevent the 

 reckless, the vicious and otherwise inferior members of 

 society from increasing at a quicker rate than the better 

 class of men,, the nation will retrograde, as has too often 

 occurred in the history of the world. We must remember 

 that progress is no invariable rule. It is very difficult to 

 say why one civilized nation rises, becomes more powerful, 

 and spreads more widely, than another; or why the same 

 nation progresses more quickly at one time than at another. 

 We can only say that it depends on an increase in the actual 

 number of the population, on the number of the men 

 endowed with high intellectual and moral faculties, as well 

 as on their standard of excellence. Corporeal structure 

 appears to have little influence, except so far as vigor of 

 body leads to vigor of mind. 



It has been urged by several writers that as high intellec- 

 tual powers are advantageous to a nation, the old Greeks, 

 who stood some grades higher in intellect than any race that 

 has ever existed,! ought, if the power of natural selection 

 were real, to have risen still higher in the scale, increased 

 in number, and stocked the whole of Europe. Here we 

 have the tacit assumption, so often made with respect to 

 corporeal structures, that there is some innate tendency 

 toward continued development in mind and body. But 

 development of all kinds depends on many concurrent 

 favorable circumstances. Natural selection acts only tenta- 

 tively. Individuals and races may have acquired certain 

 indisputable advantages, and yet have perished from failing 



*Dr. Duncan remarks ("Fecundity, Fertility," etc., 1871, p. 334) 

 on this subject: "At every age the healthy and beautiful go over 

 from the unmarried side to the married, leaving the unmarried 

 columns crowded with the sickly and unfortunate." 



f See the ingenious and original argument on this subject by Mr. 

 Gallon, " Hereditary Uenius," pp. 340-342. 



