Combining Philosophers

All the ideas for Theophrastus, Alex Orenstein and Peter Singer

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32 ideas

4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
Sentential logic is consistent (no contradictions) and complete (entirely provable) [Orenstein]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
Axiomatization simply picks from among the true sentences a few to play a special role [Orenstein]
4. Formal Logic / D. Modal Logic ML / 4. Alethic Modal Logic
S4: 'poss that poss that p' implies 'poss that p'; S5: 'poss that nec that p' implies 'nec that p' [Orenstein]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Unlike elementary logic, set theory is not complete [Orenstein]
4. Formal Logic / G. Formal Mereology / 1. Mereology
Mereology has been exploited by some nominalists to achieve the effects of set theory [Orenstein]
5. Theory of Logic / G. Quantification / 1. Quantification
Traditionally, universal sentences had existential import, but were later treated as conditional claims [Orenstein]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
The substitution view of quantification says a sentence is true when there is a substitution instance [Orenstein]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
The whole numbers are 'natural'; 'rational' numbers include fractions; the 'reals' include root-2 etc. [Orenstein]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
The logicists held that is-a-member-of is a logical constant, making set theory part of logic [Orenstein]
7. Existence / E. Categories / 3. Proposed Categories
Just individuals in Nominalism; add sets for Extensionalism; add properties, concepts etc for Intensionalism [Orenstein]
13. Knowledge Criteria / E. Relativism / 6. Relativism Critique
How can we state relativism of sweet and sour, if they have no determinate nature? [Theophrastus]
14. Science / B. Scientific Theories / 1. Scientific Theory
The Principle of Conservatism says we should violate the minimum number of background beliefs [Orenstein]
19. Language / A. Nature of Meaning / 10. Denial of Meanings
People presume meanings exist because they confuse meaning and reference [Orenstein]
19. Language / C. Assigning Meanings / 3. Predicates
Three ways for 'Socrates is human' to be true are nominalist, platonist, or Montague's way [Orenstein]
19. Language / D. Propositions / 4. Mental Propositions
If two people believe the same proposition, this implies the existence of propositions [Orenstein]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / b. Defining ethics
Ethics is universalisable - it must involve an impartial and universal view of things [Singer]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / c. Ethical intuitionism
Following an inner voice for morality is irresponsible in a rational agent [Singer]
22. Metaethics / B. Value / 2. Values / c. Life
The sanctity of a human life depends either on being of our species, or on being a person [Singer]
22. Metaethics / C. The Good / 1. Goodness / h. Good as benefit
'Marginal utility' says something is more useful if it is in short supply [Singer]
23. Ethics / B. Contract Ethics / 1. Contractarianism
Why should I do anything for posterity? What has posterity ever done for me? [Singer]
23. Ethics / D. Deontological Ethics / 1. Deontology
Conflict of rules might be avoided by greater complexity, or by a hierarchy of rules [Singer]
23. Ethics / F. Existentialism / 4. Boredom
Psychopaths may just be bored, because they cannot participate in normal emotional life [Singer]
24. Political Theory / C. Ruling a State / 4. Changing the State / c. Revolution
You can't condemn violent revolution without assessing the evils it prevents [Singer]
In Marxism the state will be superseded [Singer]
24. Political Theory / D. Ideologies / 5. Democracy / e. Democratic minorities
If 49% of the population can be wrong, so can 51% [Singer]
24. Political Theory / D. Ideologies / 9. Communism
Materialist history says we are subject to incomprehensible forces [Singer]
25. Social Practice / B. Equalities / 1. Grounds of equality
Equality of interests is a minimal principle, not implying equal treatment [Singer]
25. Social Practice / B. Equalities / 4. Economic equality
Equality of opportunity unfairly rewards those lucky enough to have great ability [Singer]
25. Social Practice / C. Rights / 1. Basis of Rights
If a right entails having the relevant desire, many creatures might have no right to life [Singer]
25. Social Practice / F. Life Issues / 3. Abortion
Why should a potential person have the rights of an actual person? [Singer]
25. Social Practice / F. Life Issues / 6. Animal Rights
Killing a chimp is worse than killing a human too defective to be a person [Singer]
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / c. Purpose denied
Theophrastus doubted whether nature could be explained teleologically [Theophrastus, by Gottschalk]