Combining Philosophers

All the ideas for Hermarchus, Augustus De Morgan and Henry Sidgwick

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8 ideas

5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
17744 De Morgan started the study of relations and their properties [De Morgan, by Walicki]
13501 De Morgan found inferences involving relations, which eluded Aristotle's syllogistic [De Morgan, by Hart,WD]
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
17743 De Morgan introduced a 'universe of discourse', to replace Boole's universe of 'all things' [De Morgan, by Walicki]
16. Persons / F. Free Will / 2. Sources of Free Will
23111 If we say that freedom depends on rationality, the irrational actions are not free [Sidgwick]
23. Ethics / A. Egoism / 1. Ethical Egoism
23059 Self-interest is not rational, if the self is just a succession of memories and behaviour [Sidgwick, by Gray]
23. Ethics / E. Utilitarianism / 1. Utilitarianism
4129 It is self-evident (from the point of view of the Universe) that no individual has more importance than another [Sidgwick]
24. Political Theory / D. Ideologies / 4. Social Utilitarianism
20588 Sidwick argues for utilitarian institutions, rather than actions [Sidgwick, by Tuckness/Wolf]
25. Social Practice / F. Life Issues / 6. Animal Rights
6005 Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley]