There is a sound physiological reason for this courtship, for in the act of wooing and being wooed the psychic excitement gradually generated in the brains of the two partners acts as a stimulant to arouse into full activity the mechanism which ensures sexual union and aids ultimate impregnation.

Such courtship is thus a fundamental natural fact.
It is as a natural fact that we still find it in full development among a large number of peoples of the lower races whom we are accustomed to regard as more primitive than ourselves.

New conditions, it is true, soon enter to complicate the picture presented by savage courtship.

The economic element of bargaining, destined to prove so important, comes in at an early stage.

And among peoples leading a violent life, and constantly fighting, it has sometimes happened, though not always, that courtship also has been violent.