which the fundamental political importance is obvious, may be derived historically and psychologically from the hoarding instinct. Love of the good opinion of others (which we may call vanity) is a desire which man shares with many animals; it is perhaps derivable from courtship, but has great survival value, among gregarious animals, in regard to others besides possible mates. Rivalry and love of power are perhaps developments of jealousy; they are akin, but not identical.
These four passions--acquisitiveness, vanity, rivalry, and love of power--are, after the basic instincts, the prime movers of almost all that happens in politics. Their operation is intensified and regularized by herd instinct. But herd instinct, by its very nature, cannot be a prime mover, since it merely causes the herd to act in unison, without determining what the united action is to be. Among men, as among other gregarious animals, the united action, in any given circumstances, is determined partly by the common passions of the herd, partly by imitation of leaders. The art of politics consists in causing the latter to prevail over the former.
Of the four passions we have enumerated, only one, namely acquisitiveness, is concerned at all directly with men's relations to their material conditions. The other three--vanity, rivalry, and love
