12 ideas
| 15375 | If terms change their designations in different states, they are functions from states to objects [Fitting] |
| Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3) | |
| A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough. |
| 15376 | Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting] |
| Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.3) |
| 15378 | Awareness logic adds the restriction of an awareness function to epistemic logic [Fitting] |
| Full Idea: Awareness logic enriched Hintikka's epistemic models with an awareness function, mapping each state to the set of formulas we are aware of at that state. This reflects some bound on the resources we can bring to bear. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) | |
| A reaction: [He cites Fagin and Halpern 1988 for this] |
| 15379 | Justication logics make explicit the reasons for mathematical truth in proofs [Fitting] |
| Full Idea: In justification logics, the logics of knowledge are extended by making reasons explicit. A logic of proof terms was created, with a semantics. In this, mathematical truths are known for explicit reasons, and these provide a measure of complexity. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.6.1) |
| 11026 | Classical logic is deliberately extensional, in order to model mathematics [Fitting] |
| Full Idea: Mathematics is typically extensional throughout (we write 3+2=2+3 despite the two terms having different meanings). ..Classical first-order logic is extensional by design since it primarily evolved to model the reasoning of mathematics. | |
| From: Melvin Fitting (Intensional Logic [2007], §1) |
| 11028 | λ-abstraction disambiguates the scope of modal operators [Fitting] |
| Full Idea: λ-abstraction can be used to abstract and disambiguate a predicate. De re is [λx◊P(x)](f) - f has the possible-P property - and de dicto is ◊[λxP(x)](f) - possibly f has the P-property. Also applies to □. | |
| From: Melvin Fitting (Intensional Logic [2007], §3.3) | |
| A reaction: Compare the Barcan formula. Originated with Church in the 1930s, and Carnap 1947, but revived by Stalnaker and Thomason 1968. Because it refers to the predicate, it has a role in intensional versions of logic, especially modal logic. |
| 15377 | Definite descriptions pick out different objects in different possible worlds [Fitting] |
| Full Idea: Definite descriptions pick out different objects in different possible worlds quite naturally. | |
| From: Melvin Fitting (Intensional Logic [2007], 3.4) | |
| A reaction: A definite description can pick out the same object in another possible world, or a very similar one, or an object which has almost nothing in common with the others. |
| 5504 | Maybe we should see persons in four dimensions, with stages or time-slices at an instant [Martin/Barresi] |
| Full Idea: Some recent philosophers have argued that we should replace the three-dimensional view of persons with a four-dimensional view according to which only time-slices, or 'stages', of persons exist at short intervals of time. | |
| From: R Martin / J Barresi (Introduction to 'Personal Identity' [2003], p.3) | |
| A reaction: At first glance this seems to neatly eliminate lots of traditional worries. But why would I want to retain my identity, if someone threatened to brainwash me. I also want to disown my inadequate earlier selves. Interesting, though. Lewis. |
| 5503 | Maybe personal identity is not vital in survival, and other continuations would suffice [Martin/Barresi] |
| Full Idea: A modern question is whether personal identity is primarily what matters in survival; that is, people might cease and be continued by others whose continuation the original people would value as much. | |
| From: R Martin / J Barresi (Introduction to 'Personal Identity' [2003], p.3) | |
| A reaction: When put like this, the proposal seems hard to grasp. It only makes sense if you don't really believe in a thing called 'personal identity'. I don't see how you can believe in it without also believing that for you it has central importance. |
| 5502 | Locke's intrinsic view of personal identity has been replaced by an externalist view [Martin/Barresi] |
| Full Idea: In modern times the Lockean intrinsic relations view of personal identity has been superseded by an extrinsic relations view (also called the 'closest-continuer' or 'externalist' view). | |
| From: R Martin / J Barresi (Introduction to 'Personal Identity' [2003], p.1) | |
| A reaction: Sounds sweeping. My suspicion is that there is a raging fashion for externalist views of everything (justification, content etc.), but this will pass. I take Parfit to be the source of the modern views. |
| 7845 | When we need to do something, we depute an inner servant to remind us of it [Proust] |
| Full Idea: Whenever we have something definite to do at a given moment, we depute a certain person inside us who is accustomed to that sort of duty to keep an eye on the clock and warn us of the time. This inner servant reminded me that Albertine was coming soon. | |
| From: Marcel Proust (Remembrance of Things Past [1922], Cities.2.1) | |
| A reaction: I think Proust is wrong that we 'depute' this servant. I think it comes as a built-in feature, and the servant could never be abandoned or sacked, no matter how poor the service. Each of us is a team, which includes servants. |
| 5505 | For Aristotle the psyche perishes with the body (except possibly 'nous') [Martin/Barresi] |
| Full Idea: In Aristotle's view, with the possible exception of 'nous' the psyche and all its parts come into being at the same time as its associated body; it is inseparable from the body, and perishes along with it. | |
| From: R Martin / J Barresi (Introduction to 'Personal Identity' [2003], p.8) | |
| A reaction: It is suggested that he thought there was only one 'nous', which all humans share (p.9). If he wants to claim that one part is immortal, he doesn't have much evidence. If psyche is the form of the body, it is bound to perish. |