...Love is the most universal, the most tremendous and the most mysterious of the cosmic forces. After centuries of tentative effort, social institutions have externally diked and canalized it. Taking advantage of this situation, the moralists have tried to submit it to rules. But in constructing their theories they have never got beyond the level of an elementary empiricism influenced by out of date conceptions of matter and the relics of old taboos. Socially, in science, business and public affairs, men p