1928. The purpose of this book is an attempt to justify the popular opinion that what is commonly described as the cave man within us plays, or may play, an important part in influencing our conduct. Contents: The Monkey's View Point; Primitive Pugnacity; The Avenger of Blood; Murder as a Habit; Murder as a Ceremony; Cannibalism; The Waning of the Cave Man Influence; The Evolution of the Human Mind; The Origin of Morality; Cave Man Influence in the French Revolution; Cave Man Influence in the Paris Commune; and Cave Man Influence in the American Revolution.