Combining Texts

All the ideas for 'Unconscious Cerebral Initiative', 'First-Order Logic' and 'Questions on Aristotle's Physics'

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14 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]
9. Objects / C. Structure of Objects / 4. Quantity of an Object
Without magnitude a thing would retain its parts, but they would have no location [Buridan]
9. Objects / E. Objects over Time / 8. Continuity of Rivers
A thing is (less properly) the same over time if each part is succeeded by another [Buridan]
14. Science / A. Basis of Science / 2. Demonstration
Induction is not demonstration, because not all of the instances can be observed [Buridan]
14. Science / C. Induction / 2. Aims of Induction
Science is based on induction, for general truths about fire, rhubarb and magnets [Buridan]
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]