The Descent of Man and Selection in Relation to Sex, Vol. I
CHAPTER II.
COMPARISON OF THE MENTAL POWERS OF MAN AND THE LOWER ANIMALS.
The difference in mental power between the highest ape and the lowest savage, immense--Certain instincts in common--The emotions--Curiosity--Imitation--Attention--Memory--Imagination-- Reason--Progressive improvement--Tools and weapons used by animals--Language--Self-consciousness--Sense of beauty--Belief in God, spiritual agencies, superstitions 34-69