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All the ideas for 'Counterpart theory and Quant. Modal Logic', 'works' and 'Negation'

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26 ideas

2. Reason / A. Nature of Reason / 9. Limits of Reason
18781 Inconsistency doesn't prevent us reasoning about some system [Mares]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
18789 Intuitionist logic looks best as natural deduction [Mares]
18790 Intuitionism as natural deduction has no rule for negation [Mares]
4. Formal Logic / E. Nonclassical Logics / 3. Many-Valued Logic
18787 Three-valued logic is useful for a theory of presupposition [Mares]
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
11022 Gentzen introduced a natural deduction calculus (NK) in 1934 [Gentzen, by Read]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
18793 Material implication (and classical logic) considers nothing but truth values for implications [Mares]
18784 In classical logic the connectives can be related elegantly, as in De Morgan's laws [Mares]
5. Theory of Logic / D. Assumptions for Logic / 1. Bivalence
18786 Excluded middle standardly implies bivalence; attacks use non-contradiction, De M 3, or double negation [Mares]
18780 Standard disjunction and negation force us to accept the principle of bivalence [Mares]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
11065 The inferential role of a logical constant constitutes its meaning [Gentzen, by Hanna]
11023 The logical connectives are 'defined' by their introduction rules [Gentzen]
11213 Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen]
18782 The connectives are studied either through model theory or through proof theory [Mares]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
18783 Many-valued logics lack a natural deduction system [Mares]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
18792 Situation semantics for logics: not possible worlds, but information in situations [Mares]
5. Theory of Logic / K. Features of Logics / 2. Consistency
18785 Consistency is semantic, but non-contradiction is syntactic [Mares]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
10067 Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
18788 For intuitionists there are not numbers and sets, but processes of counting and collecting [Mares]
9. Objects / D. Essence of Objects / 1. Essences of Objects
11976 Aristotelian essentialism says essences are not relative to specification [Lewis]
10. Modality / A. Necessity / 7. Natural Necessity
11978 Causal necessities hold in all worlds compatible with the laws of nature [Lewis]
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
11979 It doesn't take the whole of a possible Humphrey to win the election [Lewis]
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
16994 Counterpart theory is bizarre, as no one cares what happens to a mere counterpart [Kripke on Lewis]
11974 Counterparts are not the original thing, but resemble it more than other things do [Lewis]
11975 If the closest resembler to you is in fact quite unlike you, then you have no counterpart [Lewis]
11977 Essential attributes are those shared with all the counterparts [Lewis]
19. Language / C. Assigning Meanings / 2. Semantics
18791 In 'situation semantics' our main concepts are abstracted from situations [Mares]