Combining Texts

All the ideas for 'Necessary Existents', 'Human Freedom and the Self' and 'First-Order Logic'

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15 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]
16. Persons / F. Free Will / 4. For Free Will
If actions are not caused by other events, and are not causeless, they must be caused by the person [Chisholm]
16. Persons / F. Free Will / 5. Against Free Will
For Hobbes (but not for Kant) a person's actions can be deduced from their desires and beliefs [Chisholm]
If free will miraculously interrupts causation, animals might do that; why would we want to do it? [Frankfurt on Chisholm]
19. Language / D. Propositions / 3. Concrete Propositions
Propositions (such as 'that dog is barking') only exist if their items exist [Williamson]
20. Action / C. Motives for Action / 4. Responsibility for Actions
Responsibility seems to conflict with events being either caused or not caused [Chisholm]
Desires may rule us, but are we responsible for our desires? [Chisholm]
26. Natural Theory / C. Causation / 8. Particular Causation / b. Causal relata
Causation among objects relates either events or states [Chisholm]