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All the ideas for 'fragments/reports', 'Model Theory' and 'Essence and Modality'

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31 ideas

1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
My account shows how the concept works, rather than giving an analysis [Fine,K]
     Full Idea: My assimilation of essence to definition ...may not provide us with an analysis of the concept, but it does provide us with a good model of how the concept works.
     From: Kit Fine (Essence and Modality [1994], p. 3)
     A reaction: An example of the modern shift in analytic philosophy, away from the dream of given a complete analysis of a concept, towards giving an account of the concepts relationships. Compare Shoemaker in Idea 8559.
2. Reason / D. Definition / 4. Real Definition
Modern philosophy has largely abandoned real definitions, apart from sortals [Fine,K]
     Full Idea: In modern analytic philosophy we find that, as a result of sustained empiricist critique, the idea of real definition has been more or less given up (unless it be taken to be vestigially present in the notion of a sortal).
     From: Kit Fine (Essence and Modality [1994], p. 3)
     A reaction: The account of essences as falling under sortals (roughly, categorising terms) is associated with David Wiggins. Kit Fine is in the business of reviving Aristotelian real definitions, as are fans of scientific essentialism (see under 'Nature').
2. Reason / D. Definition / 6. Definition by Essence
Defining a term and giving the essence of an object don't just resemble - they are the same [Fine,K]
     Full Idea: There is an analogy between defining a term and giving the essence of an object. ..However, I am inclined to think that the two cases are not merely parallel but are, at bottom, the same.
     From: Kit Fine (Essence and Modality [1994], p.13)
     A reaction: The proposal is something like the meaning of a concept being the essence of the concept. And essence is definition. The parallel is that they both lead to necessities, either derived from objects or from concepts. Sounds good to me.
2. Reason / D. Definition / 7. Contextual Definition
The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W]
     Full Idea: Late nineteenth century mathematicians said that, although plus, minus and 0 could not be precisely defined, they could be partially 'implicitly defined' as a group. This nonsense was rejected by Frege and others, as expressed in Russell 1903.
     From: Wilfrid Hodges (Model Theory [2005], 2)
     A reaction: [compressed] This is helpful in understanding what is going on in Frege's 'Grundlagen'. I won't challenge Hodges's claim that such definitions are nonsense, but there is a case for understanding groups of concepts together.
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
Since first-order languages are complete, |= and |- have the same meaning [Hodges,W]
     Full Idea: In first-order languages the completeness theorem tells us that T |= φ holds if and only if there is a proof of φ from T (T |- φ). Since the two symbols express the same relationship, theorist often just use |- (but only for first-order!).
     From: Wilfrid Hodges (Model Theory [2005], 3)
     A reaction: [actually no spaces in the symbols] If you are going to study this kind of theory of logic, the first thing you need to do is sort out these symbols, which isn't easy!
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
|= in model-theory means 'logical consequence' - it holds in all models [Hodges,W]
     Full Idea: If every structure which is a model of a set of sentences T is also a model of one of its sentences φ, then this is known as the model-theoretic consequence relation, and is written T |= φ. Not to be confused with |= meaning 'satisfies'.
     From: Wilfrid Hodges (Model Theory [2005], 3)
     A reaction: See also Idea 10474, which gives the other meaning of |=, as 'satisfies'. The symbol is ALSO used in propositional logical, to mean 'tautologically implies'! Sort your act out, logicians.
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
|= should be read as 'is a model for' or 'satisfies' [Hodges,W]
     Full Idea: The symbol in 'I |= S' reads that if the interpretation I (about word meaning) happens to make the sentence S state something true, then I 'is a model for' S, or I 'satisfies' S.
     From: Wilfrid Hodges (Model Theory [2005], 1)
     A reaction: Unfortunately this is not the only reading of the symbol |= [no space between | and =!], so care and familiarity are needed, but this is how to read it when dealing with models. See also Idea 10477.
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Model theory studies formal or natural language-interpretation using set-theory [Hodges,W]
     Full Idea: Model theory is the study of the interpretation of any language, formal or natural, by means of set-theoretic structures, with Tarski's truth definition as a paradigm.
     From: Wilfrid Hodges (Model Theory [2005], Intro)
     A reaction: My attention is caught by the fact that natural languages are included. Might we say that science is model theory for English? That sounds like Quine's persistent message.
A 'structure' is an interpretation specifying objects and classes of quantification [Hodges,W]
     Full Idea: A 'structure' in model theory is an interpretation which explains what objects some expressions refer to, and what classes some quantifiers range over.
     From: Wilfrid Hodges (Model Theory [2005], 1)
     A reaction: He cites as examples 'first-order structures' used in mathematical model theory, and 'Kripke structures' used in model theory for modal logic. A structure is also called a 'universe'.
Models in model theory are structures, not sets of descriptions [Hodges,W]
     Full Idea: The models in model-theory are structures, but there is also a common use of 'model' to mean a formal theory which describes and explains a phenomenon, or plans to build it.
     From: Wilfrid Hodges (Model Theory [2005], 5)
     A reaction: Hodges is not at all clear here, but the idea seems to be that model-theory offers a set of objects and rules, where the common usage offers a set of descriptions. Model-theory needs homomorphisms to connect models to things,
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
First-order logic can't discriminate between one infinite cardinal and another [Hodges,W]
     Full Idea: First-order logic is hopeless for discriminating between one infinite cardinal and another.
     From: Wilfrid Hodges (Model Theory [2005], 4)
     A reaction: This seems rather significant, since mathematics largely relies on first-order logic for its metatheory. Personally I'm tempted to Ockham's Razor out all these super-infinities, but mathematicians seem to make use of them.
7. Existence / C. Structure of Existence / 4. Ontological Dependence
An object is dependent if its essence prevents it from existing without some other object [Fine,K]
     Full Idea: One object depends upon another (in one sense of the term) if its essence prevents it from existing without the other object.
     From: Kit Fine (Essence and Modality [1994], p. 2)
     A reaction: I take the interest of this to be that essences are usually thought to be intrinsic, but this seems to involve the object in necessary external relations.
9. Objects / D. Essence of Objects / 2. Types of Essence
Essences are either taken as real definitions, or as necessary properties [Fine,K]
     Full Idea: Essence has been conceived either on the model of definition, involving the 'real' as opposed to 'nominal' definitions, or it is elucidated in modal terms, located in de re cases of modal attributions (an object being necessarily a certain way).
     From: Kit Fine (Essence and Modality [1994], p. 2)
     A reaction: [compressed] Fine sets out to defend the definitional view, which derives from Aristotle, his line being that necessity depends on essence, and so cannot be used to define it. I think I agree.
9. Objects / D. Essence of Objects / 6. Essence as Unifier
Essentially having a property is naturally expressed as 'the property it must have to be what it is' [Fine,K]
     Full Idea: We have an informal way of saying an object essentially has a property, as 'the object must have the property if it is to be the object that it is', and this form of words manages to convey what we wish to convey.
     From: Kit Fine (Essence and Modality [1994], p. 4)
     A reaction: The importance of this claim is that it makes no mention of 'necessity'. Fine's view is plausible, but hard to evaluate once he has said. We seem to then divide an object's properties into identity properties, causal properties and peripheral properties.
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
Simple modal essentialism refers to necessary properties of an object [Fine,K]
     Full Idea: The simplest form of the modal account takes an object to have a property essentially just in case it is necessary that the object has the property.
     From: Kit Fine (Essence and Modality [1994], p. 3)
     A reaction: Fine wants to reverse the account, explaining necessities in terms of prior essences.
Essentialist claims can be formulated more clearly with quantified modal logic [Fine,K]
     Full Idea: With the advent of quantified modal logic, philosophers have been in a better position to formulate essentialist claims.
     From: Kit Fine (Essence and Modality [1994], p. 3)
     A reaction: A nice illustration of the role which logic plays in modern analytic philosophy. It is not an unreasonable assumption that we will understand a theoretical problem more clearly if we can articulate it more accurately.
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
Metaphysical necessity is a special case of essence, not vice versa [Fine,K]
     Full Idea: Far from viewing essence as a special case of metaphysical necessity, we should view metaphysical necessity as a special case of essence.
     From: Kit Fine (Essence and Modality [1994], p. 9)
     A reaction: This strikes me as one of the most powerful proposals in modern philosophy (even if it is a reiteration of Aristotle!).
Essence as necessary properties produces a profusion of essential properties [Fine,K, by Lowe]
     Full Idea: If an essence is a sum of essential properties (had in all possible worlds where it exists), Fine points out that it seems grossly to overgenerate essential properties ('S is either a man or a mouse', or 'S is such that 2+2=4').
     From: report of Kit Fine (Essence and Modality [1994]) by E.J. Lowe - What is the Source of Knowledge of Modal Truths? 6
     A reaction: To me this is the sort of mess you get into when you accept that 'being such that p' is a property. Defenders of the modal approach always have to eliminate 'trivial' properties from essences, but non-trivial is a defining feature of an essence.
The nature of singleton Socrates has him as a member, but not vice versa [Fine,K]
     Full Idea: Can we not recognise a sense of 'what an object is', according to which it lies in the nature of a singleton to have Socrates as a member, even though it does not lie in the nature of Socrates to belong to the singleton?
     From: Kit Fine (Essence and Modality [1994], p. 5)
     A reaction: Important and persuasive. It echoes the example in Idea 11162, that the necessary relation is not part of the essence. Socrates is necessarily in {Socrates}, but that is because of the set, not because of Socrates. Essences causes necessities.
It is not part of the essence of Socrates that a huge array of necessary truths should hold [Fine,K]
     Full Idea: Necessarily any necessary truth will hold if Socrates exists. But it is no part of Socrates' essence that there be infinitely many prime numbers, ..or that objects like the Eiffel Tower have their own necessary essence.
     From: Kit Fine (Essence and Modality [1994], p. 5-6)
     A reaction: This and the 'singleton Socrates' example (Idea 11165) are the twin prongs of Fine's attack on the modal account of essentialism. I think they constitute one of the best single pages in the whole of recent philosophy. Bravo.
9. Objects / D. Essence of Objects / 8. Essence as Explanatory
An essential property of something must be bound up with what it is to be that thing [Fine,K, by Rami]
     Full Idea: Fine's view is that the notion of an essential property of a thing should be bound up with the notion of what it is to be that thing (unlike, for example, Socrates being such that there are infinitely many primes).
     From: report of Kit Fine (Essence and Modality [1994]) by Adolph Rami - Essential vs Accidental Properties §2
     A reaction: I would think that Fine is so obviously right that it was hardly worth saying, but philosophers are a funny lot, and are quite likely to claim that features of prime numbers are part of the essence of a long-dead philosopher.
9. Objects / D. Essence of Objects / 9. Essence and Properties
Essential properties are part of an object's 'definition' [Fine,K, by Rami]
     Full Idea: According to Fine's definitional characterization of essential properties, they are those of an object's properties that are part of the object's 'definition'.
     From: report of Kit Fine (Essence and Modality [1994]) by Adolph Rami - Essential vs Accidental Properties §2
     A reaction: This demands not just an account of what a definition is, but also the notion that there is only one fixed and correct definition (since the object presumably only has one essence) - but there seems to be something relative about a good definition.
9. Objects / E. Objects over Time / 12. Origin as Essential
If Socrates lacks necessary existence, then his nature cannot require his parents' existence [Fine,K]
     Full Idea: If there is nothing in the nature of Socrates which demands that he exists, then presumably there is nothing in the nature of Socrates which demands that his parents exist.
     From: Kit Fine (Essence and Modality [1994], p. 6)
     A reaction: This sounds conclusive to me, against any claim that Socrates necessarily had those parents, if the claim is based on the identity or esssence of Socrates.
10. Modality / C. Sources of Modality / 1. Sources of Necessity
The subject of a proposition need not be the source of its necessity [Fine,K]
     Full Idea: We naturally suppose, if a subject-predicate proposition is necessary, that the subject of the proposition is the source of the necessity. But that singleton 2 contains 2 is necessary, whether the number or the set is the subject of the proposition.
     From: Kit Fine (Essence and Modality [1994], p. 9)
     A reaction: A very nice addition to his general attack on the idea that essence should be accounted for in terms of his necessity. He asks a beautifully simple question: for each necessity that we accept, what is the source of that necessity?
10. Modality / C. Sources of Modality / 4. Necessity from Concepts
Conceptual necessities rest on the nature of all concepts [Fine,K]
     Full Idea: Conceptual (and logical) necessities can be taken to be the propositions which are true in virtue of the nature of all concepts (or just the logical concepts).
     From: Kit Fine (Essence and Modality [1994], p. 9-10)
     A reaction: The idea that something might be true simply because of the nature of a concept sounds good, and a slightly better formulation than traditional accounts of analytic truth.
10. Modality / C. Sources of Modality / 6. Necessity from Essence
Metaphysical necessities are true in virtue of the nature of all objects [Fine,K]
     Full Idea: The metaphysically necessary truths can be identified with the propositions which are true in virtue of the nature of all objects whatever.
     From: Kit Fine (Essence and Modality [1994], p. 9)
     A reaction: This is part of Fine's proposal that necessities are derived from the essences or natures of things, which view I find very congenial.
Socrates is necessarily distinct from the Eiffel Tower, but that is not part of his essence [Fine,K]
     Full Idea: It is necessary that Socrates and the Eiffel Tower be distinct. But it is not essential to Socrates that he be distinct from the Tower, for there is nothing in his nature which connects him in any special way to it.
     From: Kit Fine (Essence and Modality [1994], p. 5)
     A reaction: I find this simple argument very persuasive in separating out necessary facts about an object from the essence of that object.
19. Language / E. Analyticity / 2. Analytic Truths
The meaning of 'bachelor' is irrelevant to the meaning of 'unmarried man' [Fine,K]
     Full Idea: Strictly speaking it is irrelevant to the meaning of 'bachelor' that the phrase 'unmarried man' means what it does.
     From: Kit Fine (Essence and Modality [1994], p.13)
     A reaction: His point is that the necessary truth here derives from the meaning of 'bachelor', and not from the meaning of 'unmarried man'. But is also true that 'unmarried man' means 'bachelor' (for those familiar with the latter, but not the former).
Analytic truth may only be true in virtue of the meanings of certain terms [Fine,K]
     Full Idea: Just as a necessary truth may be true in virtue of the identity of certain objects as opposed to others, so an analytic truth may be true in virtue of the meanings of certain terms as opposed to others (such as 'bachelor' rather than 'unmarried').
     From: Kit Fine (Essence and Modality [1994], p.10)
     A reaction: This is a beautifully simple observation, that the necessity of 'bachelors are unmarried men' derives from part of the proposition, not from the whole of it. So what is it about the part that generates the apparent necessity? The nature of the concept!
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]
     Full Idea: Archelaus was the first person to say that the universe is boundless.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]
     Full Idea: Archelaus wrote that life on Earth began in a primeval slime.
     From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus
     A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea.