Combining Texts

All the ideas for 'Unconscious Cerebral Initiative', 'First-Order Logic' and 'Reference and Generality (3rd ed)'

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15 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
10282 Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
10283 A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
10284 There are three different standard presentations of semantics [Hodges,W]
10285 I |= φ means that the formula φ is true in the interpretation I [Hodges,W]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
10288 Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
10289 Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
5. Theory of Logic / K. Features of Logics / 6. Compactness
10287 If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / d. Counting via concepts
12154 Are 'word token' and 'word type' different sorts of countable objects, or two ways of counting? [Geach, by Perry]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
10286 A 'set' is a mathematically well-behaved class [Hodges,W]
9. Objects / A. Existence of Objects / 6. Nihilism about Objects
8969 We should abandon absolute identity, confining it to within some category [Geach, by Hawthorne]
9. Objects / F. Identity among Objects / 3. Relative Identity
16075 Denial of absolute identity has drastic implications for logic, semantics and set theory [Wasserman on Geach]
12152 Identity is relative. One must not say things are 'the same', but 'the same A as' [Geach]
9. Objects / F. Identity among Objects / 8. Leibniz's Law
16073 Leibniz's Law is incomplete, since it includes a non-relativized identity predicate [Geach, by Wasserman]
20. Action / B. Preliminaries of Action / 2. Willed Action / a. Will to Act
7861 Libet says the processes initiated in the cortex can still be consciously changed [Libet, by Papineau]
6660 Libet found conscious choice 0.2 secs before movement, well after unconscious 'readiness potential' [Libet, by Lowe]