Primitive and civilized races, [196-202]; language, [220-21], [230]; man's manufacture of tools, [16-17]; morality, [417]; religion, [295-98], [300-01], [305], [307]; science, [61-62].

Principles, [431].

Privacy, instinctive demand for, [138].

Probability, [405-07].

Progress, and custom, [420-24]; and pugnacity, [114-15]; and reflection, [434]; and variation from normal, [144-47], [190]; science as an instrument of, [379], [407-10].

Propaganda, art as, [357-58], [362], [364]; emotional value of words in, [239].

Psychological tests. See Intelligence, measurement of.

Psychology, and ethics, [454]; behavioristic, [447]; "faculty," [39]; Freudian, [111], [164], [202]; of Utilitarianism, [446-47].

Public opinion, [22], [101], [106-07]; opposition to, [103].

Pugnacity, instinct of, [111-115].