# Tag Info

Accepted

### How do Kripke's rigid designators and the necessity of identity relate to the Duhem-Quine thesis?

They are in opposition, as Quine and Kripke generally are on interpreting modal logic, and much of what is related to it. Rigid designators are defined as those picking out the same object in all ...
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Saul Kripke died last month, after a very respected and productive philosophic career. An in depth retrospective on his contributions is a very timely request. Here are three obituaries that ...
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### Why aren't Kripke semantics "syntax in disguise"?

Algebraic semantics give a good organising framework for models of a logic, but they don’t give examples of models, except syntax itself. Kripke models give an easy way to construct lots of concrete ...
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### What are the relations between externalism (Kripke, Putnam) and holism (Quine) about meaning?

Holism is an epistemological position, and externalism is a semantic one. Of course, some degree of interaction is to be expected, but not only is it possible to hold them together, it is not ...
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Yes. Reading Kripke's works is very different than reading a math book on set theory, principally because his interests are in "meta" issues, and his works (books), are comprised of his lecture series,...

### A possible formal failure made by Kripke?

The TL;DR version is that Kripke has misunderstood Lewis’ counterpart theory, and so his criticism is off-base. The longer version follows. To understand what is going on here, it helps to have a ...
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### What is the Barcan Formula?

(◊ ∃x Fx) ↔ (∃x ◊ Fx) can be seen as a conjunction of (◊ ∃x Fx) → (∃x ◊ Fx) (the Barcan formula in the narrower sense) and (∃x ◊ Fx) → (◊ ∃x Fx) (the converse Barcan formula). ...
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### Prove or disprove ~◇◻p → ◇◇~p in system K

You surely cannot do this in System K. Instead of focusing on symbol manipulation, it's important to understand the semantics of these sentences. System K is a normal modal logic, so we may dispense ...
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### What is the relationship between Kripke's rigid designators and scientific realism?

It does make sense in a way. Kripke's thesis is that proper names have essences, properties that belong to them of necessity, not accidentally. Putnam extended this thesis to "natural kinds" of ...
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### Could Napoleon have been born to different parents?

Kripke's argument for a casual-historical view of names is first and foremost about proper names. It is a theory to explain how proper names are used in natural languages. Kripke argues that rigid ...
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### What are the relations between externalism (Kripke, Putnam) and holism (Quine) about meaning?

Conifold's answer seems to contain all the relevant materials, but I'll try to arrange them a bit differently. So yes, there seems to be a certain collision between semantic externalism and holism. ...
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### Prove or disprove ~◇◻p → ◇◇~p in system K

~◇◻P → ◇◇~P Following is the proof. - ~◇◻P - ∴ ◻~◻P - ∴ ◻◇~P From ◻◇~P we can apply an axiom from Modal System D, stating that everything that is necessary is also possible, that is if P is ...
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### A Problem With Kripke's Rule-Following Paradox Example?

The main problem with your suggestion is not philosophical but mathematical. Let's denote quus by # and plus by +. Even without any skeptical thesis, you simply cannot move from 57 # b = 5 to ...
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### A possible formal failure made by Kripke?

Long comment I'm puzzled also, but for a different reason... From (∃y) ((x) ◊(x ≠ y)), using a fresh term a, we have, by (∃-elim): (x) ◊(x ≠ a). Thus, using (∀-elim) with a (legitimate) we have: ◊(a ≠...

### Do we cause words to mean things, or do words cause us to mean things?

Do we cause words to mean things, or do words cause us to mean things? Words do not mean anything by themselves. If they did, we would not know what they meant, and if we could guess what they mean ...
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### What are the semantics for dual-intuitionistic logic?

The paper H.P. Sankappanavar, "Heyting algebras with dual pseudocomplementation", published in Pacific journal of Mathematics 117 (1985), 405–415, I believe, provides an algebraic semantics for what ...
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### Reversed Twin Earth: example from history of science

At one time planets were called "wandering stars" until it was discovered they are quite different. This is discussed on the sister site SE Astronomy at When it was discovered that the ...
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### Do we cause words to mean things, or do words cause us to mean things?

The Davidsonian View: the notions of mental content and linguistic meaning are explanatorily interdependent; neither takes explanatory priority over the other (Davidson 1984, 2001). This seems most ...
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1 vote

### Do we cause words to mean things, or do words cause us to mean things?

A rough-and-(un)ready gloss of this, on my end, is something sloganish like, "The meaning of a term 'X' is a disposition, in users of 'X,' to refer to X upon consciousness of their (or an ...
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### Why aren't Kripke semantics "syntax in disguise"?

Answer EDIT 2021-12-24 The initial presumption of my response that all model-theoretic models is wrong per the comments below. I'm letting the answer remain as the text is instructive to people such ...
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### On Searle's _Proper Names_ (1958)

From your reference below, Searle just disagree with Frege in a certain case, namely, when both a and b are proper name. His answer is that though 'a' and 'b' have the same reference they have or may ...
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### A possible formal failure made by Kripke?

I shall try explicate Kripke's footnote against the backdrop of Lewis's 1968 paper "Counterpart Theory and Quantified Modal Logic" and leave it to the reader to decide how felicitous Kripke'...
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For an overview of different things that Kripke has done, I would recommend: John Burgess: "Saul Kripke: Puzzles and Mysteries (2013),
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### Measurement units and metaphysical necessity

If a meter is the same thing in all possible worlds, we're referring to an abstract measurement, divorced from any definition that can vary. The meter has been defined as a tenth of a millionth of ...
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### How to translate classical logic to basic Kripkean logic?

There's really no translation to be done. Here's an outline of a proof. Assume P ⊨c Q. To show ⊨k 򪪪(P → Q), assume for contradiction that 򪪪(P → Q) is not valid. This means that there's a world ...
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### How to valuate (assign truth values to) a formula in modal logic (Kripke model)

Kripke models can be used to prove that a formula is not valid. Reagrading your example, this means, to show that the antecedent: (p & q → (p → q)) is true in w (the "actual" world) and the ...
1 vote

### What are the relations between externalism (Kripke, Putnam) and holism (Quine) about meaning?

Consider this analogy: Take a functionalist position in the Philosophy of Mind that says: (F) The content of each mental state is determined by its relation to other mental states, and the input-...
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### Kripke's Solution to Negative Existentials

Kripke has more recently come to hold that socalled fictional entities are real entities, and more specifically Kripke holds that e.g. Scherlock Holmes is an abstract object created by the author A.C. ...
1 vote

### What responses have made to Kripke's criticism of the descriptivist theory of meaning?

The main criticism is that were need descriptions to "know" what we're talking about, in particular in what Kripke called baptism. The first time we encounter an exemplar of a natural kind (say, a ...
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