Combining Texts

All the ideas for 'Against Coherence', 'Five Milestones of Empiricism' and 'First-Order Logic'

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19 ideas

2. Reason / D. Definition / 7. Contextual Definition
Contextual definition shifted the emphasis from words to whole sentences [Quine]
Bentham's contextual definitions preserved terms after their denotation became doubtful [Quine]
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]
12. Knowledge Sources / D. Empiricism / 1. Empiricism
In scientific theories sentences are too brief to be independent vehicles of empirical meaning [Quine]
Empiricism improvements: words for ideas, then sentences, then systems, then no analytic, then naturalism [Quine]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Incoherence may be more important for enquiry than coherence [Olsson]
Coherence is the capacity to answer objections [Olsson]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
Mere agreement of testimonies is not enough to make truth very likely [Olsson]
Coherence is only needed if the information sources are not fully reliable [Olsson]
A purely coherent theory cannot be true of the world without some contact with the world [Olsson]
Extending a system makes it less probable, so extending coherence can't make it more probable [Olsson]
19. Language / E. Analyticity / 4. Analytic/Synthetic Critique
Holism in language blurs empirical synthetic and empty analytic sentences [Quine]