Combining Texts

All the ideas for 'Unconscious Cerebral Initiative', 'First-Order Logic' and 'Intellectual Autobiography'

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19 ideas

3. Truth / B. Truthmakers / 5. What Makes Truths / a. What makes truths
Truthmakers are facts 'of' a domain, not something 'in' the domain [Sommers]
4. Formal Logic / A. Syllogistic Logic / 3. Term Logic
'Predicable' terms come in charged pairs, with one the negation of the other [Sommers, by Engelbretsen]
Logic which maps ordinary reasoning must be transparent, and free of variables [Sommers]
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 / D. Assumptions for Logic / 4. Identity in Logic
Predicate logic has to spell out that its identity relation '=' is an equivalent relation [Sommers]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
Translating into quantificational idiom offers no clues as to how ordinary thinkers reason [Sommers]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / c. not
Sommers promotes the old idea that negation basically refers to terms [Sommers, by Engelbretsen]
5. Theory of Logic / E. Structures of Logic / 7. Predicates in Logic
Predicates form a hierarchy, from the most general, down to names at the bottom [Sommers]
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]
I |= φ means that the formula φ is true in the interpretation I [Hodges,W]
There are three different standard presentations of semantics [Hodges,W]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W]
Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [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 / 2. Realism
Unfortunately for realists, modern logic cannot say that some fact exists [Sommers]
19. Language / B. Reference / 1. Reference theories
In standard logic, names are the only way to refer [Sommers]
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]