Definition of Naturalism, 20 Psychological hedonism, 21 1. Its theory of action ambiguous, 22 Referring to-- (_a_) Actual consequences of action, 23 (_b_) Or its expected consequences, 23 (_c_) Or its present characteristics, 24 2. Ethical inferences from this theory, 25 3. Transition from psychological to ethical hedonism, 31 4. Possible objections considered, 37 CHAPTER III. THE TRANSITION TO UTILITARIANISM. 1. Difference of the standpoints of individual and State, 41 2. Connection between egoism and utilitarianism according to Bentham, 45 (_a_) Utilitarianism not a political duty, 46 (_b_) Nor a moral duty, 47 (_c_) Nor insisted on as a religious duty, 49 (_d_) Nor sufficiently motived in private ethics, 50 3. Exhaustive character of Bentham's treatment from his point of view, 51 (_a_) The religious sanction (Paley), 53 (_b_) Limits of the political sanction, 54 (_c_) Uncertainty of the social sanction, 55 (_d_) And of the internal sanction so far as a result of the social, 56 4. Mill's logical defence of utilitarianism, 57 (_a_) Distinction of kinds of pleasure, 58 (_b_) Ambiguities in his proof, 60 5. Actual transition to utilitarianism, 62 (_a_) Recognition of sympathy, 64 (_b_) The idea of equality, 69 6. The two sides of utilitarian theory without logical connection, 73 7. Summary of the ethical consequences of psychological hedonism, 75 CHAPTER IV. MORAL SENTIMENT. 1. A uniform psychological theory not supplied by the opponents of ethical hedonism, 78 2. The non-hedonistic theory of action, 84 3. Ethics made to depend on the moral sense, 89 (_a_) As harmony of impulses, 90 (_b_) As a separate sensitive faculty, 92 (_c_) As an internal law, 100 4. The ethics of moral sentiment a mediating theory, 105 PART II. THE THEORY OF EVOLUTION. CHAPTER V.