228 THE POPULAR SCIENCE MONTHLY. 



informing of eye and hand rather than by the straining of thought and 

 memory. Unlike quantity, tension is not immediately dependent upon 

 physical health. Neuralgic and dyspeptic persons often possess this 

 virtue in high degree, and indeed fasting is said by spiritual teachers 

 to intensify mental action. If quantity, however, be not added to ten- 

 sion, great passion or great action is followed by utter exhaustion and 

 depression ; and, where high mettle and enduring force are combined, 

 we obtain the greatest results. Certain drugs, such as strychnine, have 

 the property of heightening the tension of nerve ; and others, such as 

 iron and cod-liver oil, of enriching it in quantity. In the combination 

 of the two kinds we have the most precious medicines. The so-called 

 " nervous children " products of a later civilization need especially 

 the benefits of quantity and control, and intelligent parents secure this 

 by restraining scholastic pressure, by enforcing a regular discipline, and 

 by encouraging physical development. 



That endowment which I have called Variety or versatility is also 

 partly innate and partly acquired, but chiefly innate. 1 It must consist 

 in the accretion of a greater number of ganglia and of interweaving 

 fibres. This is not unfavorable to quantity of nerve-force, but perhaps 

 it is unfavorable to the quality or high development of special gangli- 

 onic groups, and also to tenacity or steadfast intensity. The school- 

 master therefore abhors versatility, and that greater schoolmaster, the 

 world, grinds it to dust. "Without variety the pedant loses the sense 

 of the infinite interests and conditions of life ; with variety and without 

 penetration the dilettante is ignorant of the depths of his own igno- 

 rance. The pedant denies that any knowledge should be taken in 

 small quantities, the dilettante is repelled by the isolation of limited re- 

 search. It would seem to be the aim of good education to insist upon 

 a mastery of one or more subjects, that the grown man should be able 

 to fight with the foremost, to concentrate his powers, and to realize 

 what knowledge is, but that at the same time he should gain some not 

 inadequate notion of the whole field of the battle of life. He will thus 

 gain in sympathy and flexibility of mind, while he is saved from the 

 " failing of omniscience." A happy citizen of the republic of learning 

 must have culture at once liberal and profound, at once general and 

 special; to such a one a little knowledge is no longer a dangerous 

 thing. 



Finally, Control is partly innate, but greatly the creature of educa- 

 tion. It is, I believe, the earliest work of education, the safest work 

 and the most abiding. As an innate virtue it consists, no doubt, in 

 the superposition of more complex or higher centres upon the lower 

 and upon the weaving of these together by commissures of various 

 orders. These ganglia and fibres, sketched out as it were by inheri- 

 tance, are nourished and developed by use, i. e., by education. By use 



1 Diderot is the most brilliant instance of the Various man I can at present call to 

 mind. 



