Combining Texts

All the ideas for 'People and Their Bodies', 'Contingent Identity' and 'Modal Logic'

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


22 ideas

4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / b. System K
Normal system K has five axioms and rules [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / c. System D
D is valid on every serial frame, but not where there are dead ends [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / g. System S4
S4 has 14 modalities, and always reduces to a maximum of three modal operators [Cresswell]
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
In S5 all the long complex modalities reduce to just three, and their negations [Cresswell]
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
Reject the Barcan if quantifiers are confined to worlds, and different things exist in other worlds [Cresswell]
8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation
A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell]
9. Objects / B. Unity of Objects / 3. Unity Problems / c. Statue and clay
If a statue is identical with the clay of which it is made, that identity is contingent [Gibbard]
A 'piece' of clay begins when its parts stick together, separately from other clay [Gibbard]
Clay and statue are two objects, which can be named and reasoned about [Gibbard]
We can only investigate the identity once we have designated it as 'statue' or as 'clay' [Gibbard]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
Essentialism is the existence of a definite answer as to whether an entity fulfils a condition [Gibbard]
9. Objects / D. Essence of Objects / 15. Against Essentialism
Essentialism for concreta is false, since they can come apart under two concepts [Gibbard]
9. Objects / E. Objects over Time / 5. Temporal Parts
How can point-duration slices of people have beliefs or desires? [Thomson]
9. Objects / E. Objects over Time / 12. Origin as Essential
A particular statue has sortal persistence conditions, so its origin defines it [Gibbard]
9. Objects / F. Identity among Objects / 6. Identity between Objects
Claims on contingent identity seem to violate Leibniz's Law [Gibbard]
9. Objects / F. Identity among Objects / 8. Leibniz's Law
Two identical things must share properties - including creation and destruction times [Gibbard]
Leibniz's Law isn't just about substitutivity, because it must involve properties and relations [Gibbard]
10. Modality / A. Necessity / 4. De re / De dicto modality
A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell]
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
Possible worlds identity needs a sortal [Gibbard]
Only concepts, not individuals, can be the same across possible worlds [Gibbard]
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Kripke's semantics needs lots of intuitions about which properties are essential [Gibbard]
19. Language / B. Reference / 3. Direct Reference / b. Causal reference
Naming a thing in the actual world also invokes some persistence criteria [Gibbard]