Combining Philosophers

All the ideas for Hermarchus, G. Aldo Antonelli and Alex Orenstein

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25 ideas

2. Reason / E. Argument / 1. Argument
You can 'rebut' an argument's conclusion, or 'undercut' its premises [Antonelli]
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 / E. Nonclassical Logics / 1. Nonclassical Logics
We infer that other objects are like some exceptional object, if they share some of its properties [Antonelli]
4. Formal Logic / E. Nonclassical Logics / 12. Non-Monotonic Logic
Reasoning may be defeated by new premises, or by finding out more about the given ones [Antonelli]
Should we accept Floating Conclusions, derived from two arguments in conflict? [Antonelli]
Weakest Link Principle: prefer the argument whose weakest link is the stronger [Antonelli]
Non-monotonic core: Reflexivity, Cut, Cautious Monotonicity, Left Logical Equivalence, Right Weakening [Antonelli]
We can rank a formula by the level of surprise if it were to hold [Antonelli]
People don't actually use classical logic, but may actually use non-monotonic logic [Antonelli]
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]
5. Theory of Logic / K. Features of Logics / 10. Monotonicity
In classical logic the relation |= has Monotony built into its definition [Antonelli]
Cautious Monotony ignores proved additions; Rational Monotony fails if the addition's negation is proved [Antonelli]
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]
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]
25. Social Practice / F. Life Issues / 6. Animal Rights
Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley]