Combining Texts

All the ideas for 'Unconscious Cerebral Initiative', 'First-Order Logic' and 'Intro to 'Modality and Tense''

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19 ideas

1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Philosophers with a new concept are like children with a new toy [Fine,K]
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 / C. Structure of Existence / 7. Abstract/Concrete / a. Abstract/concrete
Possible objects are abstract; actual concrete objects are possible; so abstract/concrete are compatible [Fine,K]
7. Existence / D. Theories of Reality / 3. Reality
A non-standard realism, with no privileged standpoint, might challenge its absoluteness or coherence [Fine,K]
9. Objects / A. Existence of Objects / 3. Objects in Thought
Objects, as well as sentences, can have logical form [Fine,K]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
We must distinguish between the identity or essence of an object, and its necessary features [Fine,K]
10. Modality / A. Necessity / 3. Types of Necessity
The three basic types of necessity are metaphysical, natural and normative [Fine,K]
10. Modality / A. Necessity / 5. Metaphysical Necessity
Metaphysical necessity may be 'whatever the circumstance', or 'regardless of circumstances' [Fine,K]
10. Modality / A. Necessity / 11. Denial of Necessity
Empiricists suspect modal notions: either it happens or it doesn't; it is just regularities. [Fine,K]
19. Language / C. Assigning Meanings / 8. Possible Worlds Semantics
If sentence content is all worlds where it is true, all necessary truths have the same content! [Fine,K]
20. Action / B. Preliminaries of Action / 2. Willed Action / a. Will to Act
Libet says the processes initiated in the cortex can still be consciously changed [Libet, by Papineau]
Libet found conscious choice 0.2 secs before movement, well after unconscious 'readiness potential' [Libet, by Lowe]