It may seem as if imitation were a separate principle in mental growth, and there have been many to state this. As is well known Tarde made it a leading factor in human development. It seems to me that it is linked up with desire for experience, desire for fellowship, and also with a strongly competitive feeling, which is early manifest in children and which may be called "a want of what the other fellow has." Children at the age of a year and up may be perfectly pleased with what they have until they see another child playing with something,--something perhaps identical with their own. They then betray a decided, uncontrollable desire for the other child's toy; they are no longer content with their own, and by one means or another they seek to get it,--by forcible means, by wheedling or coaxing, or by tormenting their parents. The disappearance of contentment through the competitive feeling, the competitive nature of desire, the role that envy plays in the happiness and effort of man, is a thesis emphasized by every moralist and philosopher since the beginning of things. In the strivings of every man, though he admit it or not, one of the secret springs of his energy is this law of desire, that a large part of its power and persistence is in the competitive feeling, is in envy and the wish to taste what others are experiencing. A basic law of desire lies in an observation of Lotze, elaborated by William James. We may talk of selfishness and altruism as if they were entirely separate qualities of human nature. But what seems to be true is that one is an extension of the other, that is, we are always concerned with the ego feeling, but in the one case the ego feeling is narrow and in the other case it includes others as part of the ego. Lotze's observations on clothes shows that we expend ego feeling in all directions, that we tend to be as tall as our top hats and as penetrating as our walking sticks, that the man who has a club in his hand has a tactile sense to the very end of the club. James in his marvelous chapter on the various selves points out that a man's interests and affections are his selves, and that they enclose one another like the petals of a rose. We may speak of unipetalar selves, who include only their own bodies in self-feeling; of bipetalar selves who include in it their families, and from there on we go to selves who include their work, their community, their nation, until we reach those very rare souls whose petals cover all living things. So men extend their self-feeling, if ambitious, to their work, to their achievements,--if paternal to their children; if domestic, to wife and home; if patriotic to the nation, etc. Development lies in the extension of the self-feeling and in the increase of its intensity. But the obstacle lies in the competitive feelings, in that dualism of man's nature that makes him yearn not only for fellowship, but also for superiority. These desires are in