Combining Texts

All the ideas for 'Semantics for Propositional Attitudes', 'First-Order Logic' and 'The Problem of Consciousness'

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12 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
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
A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W]
There are three different standard presentations of semantics [Hodges,W]
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
Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W]
Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
5. Theory of Logic / K. Features of Logics / 6. Compactness
If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
A 'set' is a mathematically well-behaved class [Hodges,W]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / a. Ontological commitment
Our commitments are to an 'ontology', but also to an 'ideology', or conceptual system [Hintikka]
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
Commitment to possible worlds is part of our ideology, not part of our ontology [Hintikka]
17. Mind and Body / D. Property Dualism / 6. Mysterianism
McGinn invites surrender, by saying it is hopeless trying to imagine conscious machines [Dennett on McGinn]
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / b. Multiple realisability
Multiple realisability rules out hidden essences and experts as the source of water- and gold-concepts [McGinn]