Combining Philosophers

All the ideas for Engelbretsen,G/Sayward,C, Robert Merrihew Adams and Arend Heyting

expand these ideas     |    start again     |     specify just one area for these philosophers


22 ideas

4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward]
Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward]
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward]
4. Formal Logic / A. Syllogistic Logic / 3. Term Logic
Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward]
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Logic is dependent on mathematics, not the other way round [Heyting, by Shapiro]
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
A 'thisness' is a thing's property of being identical with itself (not the possession of self-identity) [Adams,RM]
There are cases where mere qualities would not ensure an intrinsic identity [Adams,RM]
Adams says actual things have haecceities, but not things that only might exist [Adams,RM, by Stalnaker]
9. Objects / D. Essence of Objects / 9. Essence and Properties
Essences are taken to be qualitative properties [Adams,RM]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
If the universe was cyclical, totally indiscernible events might occur from time to time [Adams,RM]
Two events might be indiscernible yet distinct, if there was a universe cyclical in time [Adams,RM]
Black's two globes might be one globe in highly curved space [Adams,RM]
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / a. Nature of possible worlds
Are possible worlds just qualities, or do they include primitive identities as well? [Adams,RM]
10. Modality / E. Possible worlds / 2. Nature of Possible Worlds / b. Worlds as fictions
Possible worlds are world-stories, maximal descriptions of whole non-existent worlds [Adams,RM, by Molnar]
10. Modality / E. Possible worlds / 3. Transworld Objects / d. Haecceitism
Adams says anti-haecceitism reduces all thisness to suchness [Adams,RM, by Stalnaker]
Haecceitism may or may not involve some logical connection to essence [Adams,RM, by Mackie,P]
Moderate Haecceitism says transworld identities are primitive, but connected to qualities [Adams,RM]
19. Language / B. Reference / 3. Direct Reference / a. Direct reference
Direct reference is by proper names, or indexicals, or referential uses of descriptions [Adams,RM]