display all the ideas for this combination of philosophers
8 ideas
10454 | In first-order we can't just assert existence, and it is very hard to deny something's existence [Bach] |
Full Idea: In standard logic we can't straightforwardly say that n exists. We have to resort to using a formula like '∃x(x=n)', but we can't deny n's existence by negating that formula, because standard first-order logic disallows empty names. | |
From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) |
10453 | In logic constants play the role of proper names [Bach] |
Full Idea: In standard first-order logic the role of proper names is played by individual constants. | |
From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) |
10452 | Proper names can be non-referential - even predicate as well as attributive uses [Bach] |
Full Idea: Like it or not, proper names have non-referential uses, including not only attributive but even predicate uses. | |
From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) | |
A reaction: 'He's a right little Hitler'. 'You're doing a George Bush again'. 'Try to live up to the name of Churchill'. |
10456 | Millian names struggle with existence, empty names, identities and attitude ascription [Bach] |
Full Idea: The familiar problems with the Millian view of names are the problem of positive and negative existential statements, empty names, identity sentences, and propositional attitude ascription. | |
From: Kent Bach (What Does It Take to Refer? [2006], 22.2 L1) | |
A reaction: I take this combination of problems to make an overwhelming case against the daft idea that the semantics of a name amounts to the actual object it picks out. It is a category mistake to attempt to insert a person into a sentence. |
10440 | An object can be described without being referred to [Bach] |
Full Idea: An object can be described without being referred to. | |
From: Kent Bach (What Does It Take to Refer? [2006], Intro) | |
A reaction: I'm not clear how this is possible for a well-known object, though it is clearly possible for a speculative object, such as a gadget I would like to buy. In the former case reference seems to occur even if the speaker is trying to avoid it. |
10444 | Definite descriptions can be used to refer, but are not semantically referential [Bach] |
Full Idea: If Russell is, as I believe, basically right, then definite descriptions are the paradigm of singular terms that can be used to refer but are not linguistically (semantically) referential. | |
From: Kent Bach (What Does It Take to Refer? [2006], 22.1 s5) | |
A reaction: I'm not sure that we can decide what is 'semantically referential'. Most of the things we refer to don't have names. We don't then 'use' definite descriptions (I'm thinking) - they actually DO the job. If we use them, we can 'use' names too? |
5740 | Second-order logic needs second-order variables and quantification into predicate position [Melia] |
Full Idea: Permitting quantification into predicate position and adding second-order variables leads to second-order logic. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: Often expressed by saying that we now quantify over predicates and relations, rather than just objects. Depends on your metaphysical commitments. |
5741 | If every model that makes premises true also makes conclusion true, the argument is valid [Melia] |
Full Idea: In first-order predicate calculus validity is defined thus: an argument is valid iff every model that makes the premises of the argument true also makes the conclusion of the argument true. | |
From: Joseph Melia (Modality [2003], Ch.2) | |
A reaction: See Melia Ch. 2 for an explanation of a 'model'. Traditional views of validity tend to say that if the premises are true the conclusion has to be true (necessarily), but this introduces the modal term 'necessarily', which is controversial. |