Combining Philosophers

All the ideas for James Rachels, Max J. Cresswell and Anil Gupta

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26 ideas

2. Reason / D. Definition / 1. Definitions
Definitions usually have a term, a 'definiendum' containing the term, and a defining 'definiens' [Gupta]
Notable definitions have been of piety (Plato), God (Anselm), number (Frege), and truth (Tarski) [Gupta]
2. Reason / D. Definition / 2. Aims of Definition
A definition needs to apply to the same object across possible worlds [Gupta]
The 'revision theory' says that definitions are rules for improving output [Gupta]
2. Reason / D. Definition / 3. Types of Definition
Traditional definitions are general identities, which are sentential and reductive [Gupta]
Traditional definitions need: same category, mention of the term, and conservativeness and eliminability [Gupta]
A definition can be 'extensionally', 'intensionally' or 'sense' adequate [Gupta]
2. Reason / D. Definition / 4. Real Definition
Chemists aim at real definition of things; lexicographers aim at nominal definition of usage [Gupta]
2. Reason / D. Definition / 6. Definition by Essence
If definitions aim at different ideals, then defining essence is not a unitary activity [Gupta]
2. Reason / D. Definition / 10. Stipulative Definition
Stipulative definition assigns meaning to a term, ignoring prior meanings [Gupta]
2. Reason / D. Definition / 11. Ostensive Definition
Ostensive definitions look simple, but are complex and barely explicable [Gupta]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Truth rests on Elimination ('A' is true → A) and Introduction (A → 'A' is true) [Gupta]
3. Truth / F. Semantic Truth / 2. Semantic Truth
A weakened classical language can contain its own truth predicate [Gupta]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / b. System K
Normal system K has five axioms and rules [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / c. System D
D is valid on every serial frame, but not where there are dead ends [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / g. System S4
S4 has 14 modalities, and always reduces to a maximum of three modal operators [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
In S5 all the long complex modalities reduce to just three, and their negations [Cresswell]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
Reject the Barcan if quantifiers are confined to worlds, and different things exist in other worlds [Cresswell]
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
The ordered pair <x,y> is defined as the set {{x},{x,y}}, capturing function, not meaning [Gupta]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
The Liar reappears, even if one insists on propositions instead of sentences [Gupta]
Strengthened Liar: either this sentence is neither-true-nor-false, or it is not true [Gupta]
8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation
A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell]
10. Modality / A. Necessity / 4. De re / De dicto modality
A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell]
25. Social Practice / F. Life Issues / 2. Euthanasia
If it is desirable that a given patient die, then moral objections to killing them do not apply [Rachels]
It has become normal to consider passive euthanasia while condemning active euthanasia [Rachels]
28. God / B. Proving God / 2. Proofs of Reason / c. Moral Argument
God must be fit for worship, but worship abandons morally autonomy, but there is no God [Rachels, by Davies,B]