28 ideas
18739 | Three stages of philosophical logic: syntactic (1905-55), possible worlds (1963-85), widening (1990-) [Horsten/Pettigrew] |
18741 | Logical formalization makes concepts precise, and also shows their interrelation [Horsten/Pettigrew] |
18744 | Models are sets with functions and relations, and truth built up from the components [Horsten/Pettigrew] |
18740 | If 'exist' doesn't express a property, we can hardly ask for its essence [Horsten/Pettigrew] |
14064 | If a statue is identical with the clay of which it is made, that identity is contingent [Gibbard] |
14066 | A 'piece' of clay begins when its parts stick together, separately from other clay [Gibbard] |
14067 | Clay and statue are two objects, which can be named and reasoned about [Gibbard] |
14069 | We can only investigate the identity once we have designated it as 'statue' or as 'clay' [Gibbard] |
14076 | Essentialism is the existence of a definite answer as to whether an entity fulfils a condition [Gibbard] |
14077 | Essentialism for concreta is false, since they can come apart under two concepts [Gibbard] |
14070 | A particular statue has sortal persistence conditions, so its origin defines it [Gibbard] |
14073 | Claims on contingent identity seem to violate Leibniz's Law [Gibbard] |
14065 | Two identical things must share properties - including creation and destruction times [Gibbard] |
14074 | Leibniz's Law isn't just about substitutivity, because it must involve properties and relations [Gibbard] |
18745 | A Tarskian model can be seen as a possible state of affairs [Horsten/Pettigrew] |
18747 | The 'spheres model' was added to possible worlds, to cope with counterfactuals [Horsten/Pettigrew] |
18748 | Epistemic logic introduced impossible worlds [Horsten/Pettigrew] |
18746 | Possible worlds models contain sets of possible worlds; this is a large metaphysical commitment [Horsten/Pettigrew] |
18750 | Using possible worlds for knowledge and morality may be a step too far [Horsten/Pettigrew] |
14072 | Possible worlds identity needs a sortal [Gibbard] |
14078 | Only concepts, not individuals, can be the same across possible worlds [Gibbard] |
14079 | Kripke's semantics needs lots of intuitions about which properties are essential [Gibbard] |
14071 | Naming a thing in the actual world also invokes some persistence criteria [Gibbard] |
6613 | The natural kinds are objects, processes and properties/relations [Ellis] |
6616 | Least action is not a causal law, but a 'global law', describing a global essence [Ellis] |
6615 | A species requires a genus, and its essence includes the essence of the genus [Ellis] |
6614 | A hierarchy of natural kinds is elaborate ontology, but needed to explain natural laws [Ellis] |
6612 | Without general principles, we couldn't predict the behaviour of dispositional properties [Ellis] |