Combining Texts

All the ideas for 'Bayesianism', 'First-Order Logic' and 'Naming and Necessity preface'

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18 ideas

4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
Possible worlds allowed the application of set-theoretic models to modal logic [Kripke]
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 / F. Referring in Logic / 1. Naming / c. Names as referential
A man has two names if the historical chains are different - even if they are the same! [Kripke]
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 / F. Identity among Objects / 1. Concept of Identity
With the necessity of self-identity plus Leibniz's Law, identity has to be an 'internal' relation [Kripke]
9. Objects / F. Identity among Objects / 8. Leibniz's Law
The indiscernibility of identicals is as self-evident as the law of contradiction [Kripke]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
I don't think possible worlds reductively reveal the natures of modal operators etc. [Kripke]
10. Modality / D. Knowledge of Modality / 2. A Priori Contingent
The very act of designating of an object with properties gives knowledge of a contingent truth [Kripke]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
Instead of talking about possible worlds, we can always say "It is possible that.." [Kripke]
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
Probability with dice uses possible worlds, abstractions which fictionally simplify things [Kripke]
14. Science / C. Induction / 6. Bayes's Theorem
Bayes' theorem explains why very surprising predictions have a higher value as evidence [Horwich]
Probability of H, given evidence E, is prob(H) x prob(E given H) / prob(E) [Horwich]