THE PROBLEM OF POPULATION. 677 



of members of 112 different families, of which only 58 were in exist- 

 ence in a century and a half afterward. 



If we consider special cases of noted men, the great generals of the 

 world, the commanding statesmen, the distinguished scientists, the 

 celebrated authors — all, in fact, who have become distinguished for 

 superior mental ability — an almost universal result appears : they have 

 either left no descendants, or their families were very small. And, 

 for that matter, we need but to look at evidences everywhere sur- 

 rounding us. We think it will be found to be a general rule that per- 

 sons constantly exercised in mental labor have few or no children ; 

 those of less active minds have larger families ; while the largest fami- 

 lies belong to those who do not trouble themselves to think at all. 



There is abundant reason to believe, then, that such a physiological 

 check to population really exists ; and, in its operation, it is not diffi- 

 cult to perceive a rich promise for the future of the human race. For 

 it is in no sense, in its superior phase, a starvation check. Nor does it 

 need any of the violent repression of natural desires exercised in the 

 prudential check. At first sight, it appears as if its tendency must be 

 to constantly place the cultured at a disadvantage in numbers as com- 

 pared with the dull and ignorant. But this disadvantage is more than 

 counterbalanced by the progress of education and the brain-incite- 

 ments of modern civilization. Thus, the class of brain-workers is 

 being continually recruited, despite its lack of fecundity, and we can 

 see indications of an immense future augmentation of this class of the 

 population at the expense of the unthinking, and consequently of a 

 new barrier to the progress of population, whose efficacy is now but 

 beginning to appear. 



It is a process which must in time do away with the " starvation 

 check " to population, and replace it with a new and far more desirable 

 limiting principle. For when nerve-energy largely replaces muscular 

 energy, and advanced education greatly increases the percentage of ' 

 the cultured, there may be a corresponding decrease in the birth-rate, 

 through the operation of the causes just considered. And, as human 

 want decreases and comfort advances, the developed needs of man- 

 kind must extend the prudential check on early marriage, which is so 

 active now in the middle classes. In this another limiting force will 

 be brought to bear upon the increase of population. 



Thus, as the sum of human wealth increases, through the exercise 

 of intelligence in industrial operations, it will necessarily be divided 

 among a population not increasing in an equal ratio. The average 

 wealth of all classes of the community must increase in consequence, 

 the necessary amount of active muscular labor be reduced, and more 

 time be given for rest, enjoyment, or indulgence in mental culture. 



The more rapidly that wealth accumulates in proportion to popula- 

 tion, and, the more vigorously that culture forces its way downward 

 through the community, the greater must be the effect of the pruden- 



