much in human life depends. _Shyness_ and _sociability_, _play_, _curiosity_, _acquisitiveness_, all begin very early in life. The _hunting instinct_, _modesty_, _love_, the _parental instinct_, etc., come later. By the age of 15 or 16 the whole array of human instincts is complete. It will be observed that _no other mammal, not even the monkey, shows so large a list_. In a perfectly-rounded development every one of these instincts would start a habit toward certain objects and inhibit a habit towards certain others. Usually this is the case; but, in the one-sided development of civilized life, it happens that the timely age goes by in a sort of starvation of objects, and the individual then grows up with gaps in his psychic constitution which future experiences can never fill. Compare the accomplished gentleman with the poor artisan or tradesman of a city: during the adolescence of the former, objects appropriate to his growing interests, bodily and mental, were offered as fast as the interests awoke, and, as a consequence, he is armed and equipped at every angle to meet the world. Sport came to the rescue and completed his education where real things were lacking. He has tasted of the essence of every side of human life, being sailor, hunter, athlete, scholar, fighter, talker, dandy, man of affairs, etc., all in one. Over the city poor boy's youth no such golden opportunities were hung, and in his manhood no desires for most of them exist. Fortunate it is for him if gaps are the only anomalies his instinctive life presents; perversions are too often the fruit of his unnatural bringing-up. =Description of Fear.=--In order to treat at least one instinct at greater length, I will take the instance of _fear_.