Ideas of Timothy Williamson, by Theme

[British, b.1955, Wykeham Professor of Logic at the Oxford University. Fellow of New College.]

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1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / e. Philosophy as reason
Progress in philosophy is incremental, not an immature seeking after drama
     Full Idea: The incremental progress which I envisage for philosophy lacks the drama after which some philosophers still hanker, and that hankering is itself a symptom of the intellectual immaturity that helps hold philosophy back.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], Intro)
     A reaction: This could stand as a motto for the whole current profession of analytical philosophy. It means that if anyone attempts to be dramatic they can make their own way out. They'll find Kripke out there, smoking behind the dustbins.
1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
We can't presume that all interesting concepts can be analysed
     Full Idea: We have no prior reason to suppose that philosophically significant concepts have interesting analyses into necessary and sufficient conditions.
     From: Timothy Williamson (Review of Bob Hale's 'Abstract Objects' [1988])
     A reaction: We might think that they are either analysable or primitive, and that failure of analysis invites us to take a concept as primitive. But maybe God can analyse it and we can't.
1. Philosophy / H. Continental Philosophy / 1. Continental Philosophy
Analytic philosophy has much higher standards of thinking than continental philosophy
     Full Idea: Certain advances in philosophical standards have been made within analytic philosophy, and there would be a serious loss of integrity involved in abandoning them in the way required to participate in current continental philosophy.
     From: Timothy Williamson (Interview with Baggini and Stangroom [2001], p.151)
     A reaction: The reply might be to concede the point, but say that the precision and rigour achieved are precisely what debar analytical philosophy from thinking about the really interesting problems. One might as well switch to maths and have done with it.
3. Truth / A. Truth Problems / 5. Truth Bearers
Truth and falsity apply to suppositions as well as to assertions
     Full Idea: The notion of truth and falsity apply to suppositions as well as to assertions.
     From: Timothy Williamson (Vagueness [1994], 7.2)
     A reaction: This may not be obvious to those who emphasise pragmatics and ordinary language, but it is self-evident to anyone who emphasises logic.
3. Truth / A. Truth Problems / 7. Falsehood
True and false are not symmetrical; false is more complex, involving negation
     Full Idea: The concepts of truth and falsity are not symmetrical. The asymmetry is visible in the fundamental principles governing them, for F is essentially more complex than T, by its use of negation.
     From: Timothy Williamson (Vagueness [1994], 7.5)
     A reaction: If T and F are primitives, controlled by axioms, then they might be symmetrical in nature, but asymmetrical in use. However, if forced to choose just one primitive, I presume it would be T.
3. Truth / B. Truthmakers / 5. What Makes Truths / b. Objects make truths
The truthmaker principle requires some specific named thing to make the difference
     Full Idea: The truthmaker principle seems compelling, because if a proposition is true, something must be different from a world in which it is false. The principle makes this specific, by treating 'something' as a quantifier binding a variable in name position.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §2)
     A reaction: See Williamson for an examination of the logical implications of this. The point is that the principle seems to require some very specific 'thing', which may be asking too much. For a start, it might be the absence of a thing.
3. Truth / B. Truthmakers / 7. Making Modal Truths
The converse Barcan formula will not allow contingent truths to have truthmakers
     Full Idea: The converse Barcan formula does not allow any contingent truths at all to have a truthmaker. Once cannot combine the converse Barcan formula with any truthmaker principle worth having.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §3)
     A reaction: One might reply, so much the worse for the converse Barcan formula, but Williamson doesn't think that.
Truthmaker is incompatible with modal semantics of varying domains
     Full Idea: Friends of the truthmaker principle should reject the Kripke semantics of varying domains.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §3)
     A reaction: See other ideas from this paper to get a sense of what that is about.
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
Correspondence to the facts is a bad account of analytic truth
     Full Idea: Even if talk of truth as correspondence to the facts is metaphorical, it is a bad metaphor for analytic truth in a way that it is not for synthetic truth.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], 3.1)
     A reaction: A very simple and rather powerful point. Maybe the word 'truth' should be withheld from such cases. You might say that accepted analytic truths are 'conventional'. If that is wrong, then they correspond to natural facts at a high level of abstraction.
4. Formal Logic / D. Modal Logic ML / 3. Modal Logic Systems / h. System S5
If metaphysical possibility is not a contingent matter, then S5 seems to suit it best
     Full Idea: In S5, necessity and possibility are not themselves contingent matters. This is plausible for metaphysical modality, since metaphysical possibility, unlike practical possibility, does not depend on the contingencies of one's situation.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §1)
     A reaction: This is the clearest statement I have found of why S5 might be preferable for metaphysics. See Nathan Salmon for the rival view. Williamson's point sounds pretty persuasive to me.
In S5 matters of possibility and necessity are non-contingent
     Full Idea: In system S5 matters of possibility and necessity are always non-contingent.
     From: Timothy Williamson (Modal Logic within Counterfactual Logic [2010], 3)
     A reaction: This will be because if something is possible in one world (because it can be seen to be true in some possible world) it will be possible for all worlds (since they can all see that world in S5).
4. Formal Logic / D. Modal Logic ML / 7. Barcan Formula
If the domain of propositional quantification is constant, the Barcan formulas hold
     Full Idea: If the domain of propositional quantification is constant across worlds, the Barcan formula and its converse hold.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §2)
     A reaction: So the issue is whether we should take metaphysics to be dealing with a constant or varying domains. Williamson seems to favour the former, but my instincts incline towards the latter.
Converse Barcan: could something fail to meet a condition, if everything meets that condition?
     Full Idea: The converse Barcan is at least plausible, since its denial says there is something that could fail to meet a condition when everything met that condition; but how could everything meet that condition if that thing did not?
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §3)
     A reaction: Presumably the response involves a discussion of domains, since everything in a given domain might meet a condition, but something in a different domain might fail it.
If a property is possible, there is something which can have it
     Full Idea: Barcan's axiom says if there can be something that has a certain property, then there is something that can have that property. It and its converse are not obviously correct or incorrect. They claim that it is non-contingent what individuals there are.
     From: Timothy Williamson (Laudatio: Prof Ruth Barcan Marcus [2011], p.1)
     A reaction: Williamson defends the two Barcan formulas, but the more I understand them the less plausible they sound to me.
4. Formal Logic / E. Nonclassical Logics / 3. Many-Valued Logic
Many-valued logics don't solve vagueness; its presence at the meta-level is ignored
     Full Idea: It is an illusion that many-valued logic constitutes a well-motivated and rigorously worked out theory of vagueness. ...[top] There has been a reluctance to acknowledge higher-order vagueness, or to abandon classical logic in the meta-language.
     From: Timothy Williamson (Vagueness [1994], 4.12)
4. Formal Logic / E. Nonclassical Logics / 4. Fuzzy Logic
Fuzzy logic uses a continuum of truth, but it implies contradictions
     Full Idea: Fuzzy logic is based on a continuum of degrees of truth, but it is committed to the idea that it is half-true that one identical twin is tall and the other twin is not, even though they are the same height.
     From: Timothy Williamson (Interview with Baggini and Stangroom [2001], p.154)
     A reaction: Maybe to be shocked by a contradiction is missing the point of fuzzy logic? Half full is the same as half empty. The logic does not say the twins are different, because it is half-true that they are both tall, and half-true that they both aren't.
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Formal logic struck me as exactly the language I wanted to think in
     Full Idea: As soon as I started learning formal logic, that struck me as exactly the language that I wanted to think in.
     From: Timothy Williamson (Interview with Baggini and Stangroom [2001])
     A reaction: It takes all sorts… It is interesting that formal logic might be seen as having the capacity to live up to such an aspiration. I don't think the dream of an ideal formal language is dead, though it will never encompass all of reality. Poetic truth.
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
Formal semantics defines validity as truth preserved in every model
     Full Idea: An aim of formal semantics is to define in mathematical terms a set of models such that an argument is valid if and only if it preserves truth in every model in the set, for that will provide us with a precise standard of validity.
     From: Timothy Williamson (Vagueness [1994], 5.3)
5. Theory of Logic / D. Assumptions for Logic / 1. Bivalence
'Bivalence' is the meta-linguistic principle that 'A' in the object language is true or false
     Full Idea: The meta-logical law of excluded middle is the meta-linguistic principle that any statement 'A' in the object language is either truth or false; it is now known as the principle of 'bivalence'.
     From: Timothy Williamson (Vagueness [1994], 5.2)
     A reaction: [He cites Henryk Mehlberg 1958] See also Idea 21605. Without this way of distinguishing bivalence from excluded middle, most discussions of them strikes me as shockingly lacking in clarity. Personally I would cut the normativity from this one.
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded Middle is 'A or not A' in the object language
     Full Idea: The logical law of excluded middle (now the standard one) is the schema 'A or not A' in the object-language.
     From: Timothy Williamson (Vagueness [1994], 5.2)
     A reaction: [He cites Henryk Mehlberg 1958] See Idea 21606. The only sensible way to keep Excluded Middle and Bivalence distinct. I would say: (meta-) only T and F are available, and (object) each proposition must have one of them. Are they both normative?
5. Theory of Logic / G. Quantification / 1. Quantification
Not all quantification is either objectual or substitutional
     Full Idea: We should not assume that all quantification is either objectual or substitutional.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], p.262)
     A reaction: [see Prior 1971:31-4] He talks of quantifying into sentence position.
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
Substitutional quantification is metaphysical neutral, and equivalent to a disjunction of instances
     Full Idea: If quantification into sentence position is substitutional, then it is metaphysically neutral. A substitutionally interpreted 'existential' quantification is semantically equivalent to the disjunction (possibly infinite) of its substitution instances.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §2)
     A reaction: Is it not committed to the disjunction, just as the objectual reading commits to objects? Something must make the disjunction true. Or is it too verbal to be about reality?
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
Not all quantification is objectual or substitutional
     Full Idea: We should not assume that all quantification is objectual or substitutional.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §2)
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
Or-elimination is 'Argument by Cases'; it shows how to derive C from 'A or B'
     Full Idea: Argument by Cases (or or-elimination) is the standard way of using disjunctive premises. If one can argue from A and some premises to C, and from B and some premises to C, one can argue from 'A or B' and the combined premises to C.
     From: Timothy Williamson (Vagueness [1994], 5.3)
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / b. The Heap paradox ('Sorites')
A sorites stops when it collides with an opposite sorites
     Full Idea: A sorites paradox is stopped when it collides with a sorites paradox going in the opposite direction. That account will not strike a logician as solving the sorites paradox.
     From: Timothy Williamson (Vagueness [1994], 3.3)
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
Platonism claims that some true assertions have singular terms denoting abstractions, so abstractions exist
     Full Idea: The Fregean argument for platonism is that some true assertions contain singular terms which denote abstract objects if they denote anything; since the assertions are true, the singular terms denote.
     From: Timothy Williamson (Review of Bob Hale's 'Abstract Objects' [1988])
     A reaction: I am perplexed that anyone would rest their view of reality on such an argument. The obvious comparison would be with true remarks about blatantly fictional characters, or blatantly invented concepts such as 'checkmate'.
7. Existence / D. Theories of Reality / 4. Anti-realism
The realist/anti-realist debate is notoriously obscure and fruitless
     Full Idea: The debate between realism and anti-realism has become notorious in the rest of philosophy for its obscurity, convolution, and lack of progress.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], After)
     A reaction: I find this reassuring, because fairly early on I decided that this problem was not of great interest, and quietly tiptoed away. I take the central issue to be whether nature has 'joints', to which the answer appears to be 'yes'. End of story.
7. Existence / D. Theories of Reality / 8. Facts / a. Facts
If 'fact' is a noun, can we name the fact that dogs bark 'Mary'?
     Full Idea: If one uses 'fact' as a noun, the question arises why one cannot name the fact that dogs bark 'Mary'.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §2 n10)
     A reaction: What an intriguing thought! Must all nouns pass this test? 'The courage of the regiment was called Alfred'?
7. Existence / D. Theories of Reality / 10. Vagueness / a. Problem of vagueness
Vagueness undermines the stable references needed by logic
     Full Idea: Logic requires expressions to have the same referents wherever they occur; vague natural languages violate this contraint.
     From: Timothy Williamson (Vagueness [1994], 2.2)
     A reaction: This doesn't mean that logic has to win. Maybe it is important for philosophers who see logic as central to be always aware of vagueness as the gulf between their precision and the mess of reality. Precision is worth trying for, though.
When bivalence is rejected because of vagueness, we lose classical logic
     Full Idea: The principle of bivalence (that every statement is either true or false) has been rejected for vague languages. To reject bivalence is to reject classical logic or semantics.
     From: Timothy Williamson (Vagueness [1994], Intro)
     A reaction: His example is specifying a moment when Rembrandt became 'old'. This is the number one reason why the problem of vagueness is seen as important. Is the rejection of classical logic a loss of our grip on the world?
A vague term can refer to very precise elements
     Full Idea: Both 30° and 60° are clearly acute angles. 'Acute' is precise in all relevant respects. Nevertheless, 30° is acuter than 60°.
     From: Timothy Williamson (Vagueness [1994], 4.11)
     A reaction: A very nice example of something which is vague, despite involving precise ingredients. But then 'bald' is vague, while 'this is a hair on his head' is fairly precise.
7. Existence / D. Theories of Reality / 10. Vagueness / b. Vagueness of reality
Equally fuzzy objects can be identical, so fuzziness doesn't entail vagueness
     Full Idea: Fuzzy boundaries do not in any way require vague identity. Objects are identical only if their boundaries have exactly the same fuzziness.
     From: Timothy Williamson (Vagueness [1994], 9.2)
     A reaction: This all rests on the Fregean idea that determinate existence requires the ability to participate in an identity statement.
There cannot be vague objects, so there may be no such thing as a mountain
     Full Idea: It is sometimes argued that if there is such a thing as a mountain it would be a vague object, but it is logically impossible for an object to be vague, so there is no such thing as a mountain.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], 7.2)
     A reaction: I don't take this to be a daft view. No one is denying the existence of the solid rock that is involved, but allowing such a vague object may be a slippery slope to the acceptance of almost anything as an 'object'.
7. Existence / D. Theories of Reality / 10. Vagueness / c. Vagueness as ignorance
Vagueness is epistemic. Statements are true or false, but we often don't know which
     Full Idea: My thesis is that vagueness is an epistemic phenomenon. In cases of unclarity, statements remain true or false, but speakers of the language have no way of knowing which. Higher-order vagueness consists in ignorance about ignorance.
     From: Timothy Williamson (Vagueness [1994], Intro)
     A reaction: He has plumped for the intuitively least plausible theory. It means that a hair dropping out of someone's head triggers a situation where they are 'bald', but none of us know when that was. And Rembrandt became 'old' in an instant.
If a heap has a real boundary, omniscient speakers would agree where it is
     Full Idea: If, in judging a heap as grains are removed, omniscient speakers all stop at the same point, it must does mark some sort of previously hidden boundary. ...If there is no hidden boundary, then different omniscient speakers would stop at different points.
     From: Timothy Williamson (Vagueness [1994], 7.3)
     A reaction: A very nice thought experiment, which obviously won't settle anything, but brings out nicely the view the vagueness is a sort of ignorance. God is never vague in the application of terms (though God might withhold the application if there is no boundary).
The epistemic view says that the essence of vagueness is ignorance
     Full Idea: The epistemic view is that ignorance is the real essence of the phenomenon ostensively identified as vagueness. ...[203] According to the epistemic view, I am either thin or not thin, ...and we have no idea how to find out out which.
     From: Timothy Williamson (Vagueness [1994], 7.4)
     A reaction: Presumably this implies that there is often a real border (of which we may be ignorant), but it doesn't seem to rule out cases where there just is no border. Where does the east Atlantic meet the west Atlantic?
If there is a true borderline of which we are ignorant, this drives a wedge between meaning and use
     Full Idea: A common complaint against the epistemic view is that to postulate a matter of fact in borderline cases is to suppose, incoherently, that the meanings of our words draw a line where our use of them does not.
     From: Timothy Williamson (Vagueness [1994], 7.5)
     A reaction: This doesn't necessarily seem to require the view that the meaning of words is their usage. Just that if there is one consensus on usage, it seems unlikely that there is a different underlying reality about the true meaning. Externalist meanings?
Vagueness in a concept is its indiscriminability from other possible concepts
     Full Idea: Vagueness in a concept is its indiscriminability from other possible concepts; this can be reconciled with our knowledge of vague terms.
     From: Timothy Williamson (Vagueness [1994], 8.1)
     A reaction: Sorensen objects that this makes vagueness too relative to members of a speech community. He prefers 'absolute borderline cases'. If you like the epistemic view, then Williamson seems more plausible. My 'vague' might differ from yours.
Close to conceptual boundaries judgement is too unreliable to give knowledge
     Full Idea: If one is very close to a conceptual boundary, then one's judgement will be too unreliable to constitute knowledge, and therefore one will be ignorant.
     From: Timothy Williamson (Interview with Baggini and Stangroom [2001], p.156)
     A reaction: This is the epistemological rather than ontological interpretation of vagueness. It sounds very persuasive, but I am reluctant to accept that reality is full of very precise boundaries which we cannot quite discriminate.
7. Existence / D. Theories of Reality / 10. Vagueness / d. Vagueness as linguistic
The vagueness of 'heap' can remain even when the context is fixed
     Full Idea: Vagueness remains even when the context is fixed. In principle, a vague word might exhibit no context dependence whatsoever. ...For example, a dispute over whether someone has left a 'heap' of sand on the floor.
     From: Timothy Williamson (Vagueness [1994], 7.7)
     A reaction: A fairly devastating rebuttal of what seems to be David Lewis's view. He talks of something being 'smooth' depending on context.
The 'nihilist' view of vagueness says that 'heap' is not a legitimate concept
     Full Idea: The 'nihilist' view is that no genuine distinction can be vaguely drawn; since vague expressions are not properly meaningful, there is nothing for sorites reasoning to betray; they are empty.
     From: Timothy Williamson (Vagueness [1994], 6.1)
     A reaction: He cites Frege as holding this view. The thought is that 'heap' is not a legitimate concept, so fussing over what qualifies as one is pointless. This seems to be a semantic view of vagueness, of which the main rival is the contextual view.
We can say propositions are bivalent, but vague utterances don't express a proposition
     Full Idea: A philosopher might endorse bivalence for propositions, while treating vagueness as the failure of an utterance to express a unique proposition.
     From: Timothy Williamson (Vagueness [1994], 7.2)
     A reaction: This idea jumps at out me as an extremely promising approach to vagueness, because I am a fan of propositions (and have written a paper on them). The whole point of propositions is that they are not ambiguous (and probably not vague).
If the vague 'TW is thin' says nothing, what does 'TW is thin if his perfect twin is thin' say?
     Full Idea: If vague utterances in borderline cases fail to say anything, then if 'TW is thin' is vague, and TW has a twin of identical dimensions, it still seems that 'If TW is thin then his twin is thin' must be true, and so it must have said something.
     From: Timothy Williamson (Vagueness [1994], 7.2 (d))
     A reaction: This an objection to the Fregean 'nihilistic' view of Idea 21614. I am inclined to a solution based on the proposition expressed, rather than the sentence. The first question is whether you are willing to assert 'TW is thin'.
7. Existence / D. Theories of Reality / 10. Vagueness / e. Higher-order vagueness
Asking when someone is 'clearly' old is higher-order vagueness
     Full Idea: Difficulties of vagueness are presented by the question 'When did Rembrandt become clearly old?', and the iterating question 'When did he become clearly clearly old?'. This is the phenomenon of higher-order vagueness. The language of vagueness is vague.
     From: Timothy Williamson (Vagueness [1994], Intro)
     A reaction: [compressed] I presume the bottom level is a question about Rembrandt, the second level is about this use of the word 'old', and the third level is about this particular application of the word 'clearly'. Meta-languages.
7. Existence / D. Theories of Reality / 10. Vagueness / f. Supervaluation for vagueness
Supervaluation keeps classical logic, but changes the truth in classical semantics
     Full Idea: Supervaluationism preserves almost all of classical logic, at the expense of classical semantics, but giving a non-standard account of truth. I argue that its treatment of higher-order vagueness undermines the non-standard account of truth.
     From: Timothy Williamson (Vagueness [1994], Intro)
You can't give a precise description of a language which is intrinsically vague
     Full Idea: If a vague language is made precise, its expressions change in meaning, so an accurate semantic description of the precise language is inaccurate as a description of the vague one.
     From: Timothy Williamson (Vagueness [1994], 5.1)
     A reaction: Kind of obvious, really, but it clarifies the nature of any project (starting with Leibniz) to produce a wholly precise language. That is usually seen as a specialist language for science.
Supervaluation assigns truth when all the facts are respected
     Full Idea: 'Admissible' interpretations respect all the theoretical and ostensive connections. ...'Supervaluation' is the assignment of truth to the statements true on all admissible valuations, falsity to the false one, and neither to the rest.
     From: Timothy Williamson (Vagueness [1994], 5.2)
     A reaction: So 'he is bald' is true if when faced with all observations and definitions it is acceptable. Prima facie, that doesn't sound like a solution to the problem. Supervaluation started in philosophy of science. [p.156 'Admissible seems vague']
Supervaluation has excluded middle but not bivalence; 'A or not-A' is true, even when A is undecided
     Full Idea: The supervaluationist denies bivalence but accepts excluded middle. The statement 'A or not-A' is true on each admissible interpretation, and therefore true, even if 'A' (and hence 'not-A') are true and some and false on others, so neither T nor F.
     From: Timothy Williamson (Vagueness [1994], 5.2)
     A reaction: See Ideas 21605 and 21606 for the distinction being used here. Denying bivalence allows 'A' to be neither true nor false. It seems common sense that 'he is either bald or not-bald' is true, without being sure about the disjuncts.
Truth-functionality for compound statements fails in supervaluation
     Full Idea: A striking fearure of supervaluations is the failure of truth-functionality for compound statements.
     From: Timothy Williamson (Vagueness [1994], 5.3)
     A reaction: Supervaluations has the initial appearance of enhancing classical logic, but turns out to somewhat undermine it. Hence Williamson's lack of sympathy. But see Idea 21610.
Supervaluationism defines 'supertruth', but neglects it when defining 'valid'
     Full Idea: Supervaluationists identify truth with 'supertruth'; since validity is necessary preservation of truth, they should identify it with necessary preservation of supertruth. But it plays no role in their definition of 'local' validity.
     From: Timothy Williamson (Vagueness [1994], 5.3)
     A reaction: [See text for 'local'] Generally Williamson's main concern with attempts to sort out vagueness is that higher-order and meta-language issues are neglected.
Supervaluation adds a 'definitely' operator to classical logic
     Full Idea: Supervaluation seems to inherit the power of classical logic, ...but also enables it to be extended. It makes room for a new operator 'definitely' to express supertruth in the object-language.
     From: Timothy Williamson (Vagueness [1994], 5.3)
     A reaction: Once you mention higher-order vagueness you can see a regress looming over the horizon. 'He is definitely definitely definitely bald'. [p.164 he says 'definitely' has no analysis, and is an uninteresting primitive]
Supervaluationism cannot eliminate higher-order vagueness
     Full Idea: Supervaluationism cannot eliminate higher-order vagueness. It must conduct its business in a vague meta-language. ...[162] All truth is at least disquotational, and supertruth is not.
     From: Timothy Williamson (Vagueness [1994], 5.6)
     A reaction: This is Williamson's final verdict on the supervaluation strategy for vagueness. Intuitively, it looks as if merely narrowing down the vagueness (by some sort of consensus) is no solution to the problem of vagueness.
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
Nominalists suspect that properties etc are our projections, and could have been different
     Full Idea: The nominalist suspects that properties, relations and states of affairs are mere projections onto the world of our forms of speech. One source of the suspicion is a sense that we could just as well have classified things differently.
     From: Timothy Williamson (Vagueness [1994], 9.3)
     A reaction: I know it is very wicked to say so, but I'm afraid I have some sympathy with this view. But I like the primary/secondary distinction, so there is more 'projection' in the latter case. Classification is not random; it is a response to reality.
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
If fuzzy edges are fine, then why not fuzzy temporal, modal or mereological boundaries?
     Full Idea: If objects can have fuzzy spatial boundaries, surely they can have fuzzy temporal, modal or mereological boundaries too.
     From: Timothy Williamson (Vagueness [1994], 9.2)
     A reaction: Fair point. I think there is a distinction between parts of the thing, such as its edges, being fuzzy, and the whole thing being fuzzy, in the temporal case.
What sort of logic is needed for vague concepts, and what sort of concept of truth?
     Full Idea: The problem of vagueness is the problem of what logic is correct for vague concepts, and correspondingly what notions of truth and falsity are applicable to vague statements (does one need a continuum of degrees of truth, for example?).
     From: Timothy Williamson (Interview with Baggini and Stangroom [2001], p.153)
     A reaction: This certainly makes vagueness sound like one of the most interesting problems in all of philosophy, though also one of the most difficult. Williamson's solution is that we may be vague, but the world isn't.
Common sense and classical logic are often simultaneously abandoned in debates on vagueness
     Full Idea: The constraints of common sense and classical logic are often simultaneously abandoned in debates on vagueness.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], After)
     A reaction: Wiliamson has described himself (in my hearing) as a 'rottweiller realist', but presumably the problem of vagueness interests a lot of people precisely because it pushes us away from common sense and classical logic.
9. Objects / E. Objects over Time / 8. Continuity of Rivers
A river is not just event; it needs actual and counterfactual boundaries
     Full Idea: A river is not just an event. One would need to specify counterfactual as well as actual boundaries.
     From: Timothy Williamson (Vagueness [1994], 9.3)
     A reaction: In other words the same river can change its course a bit, but it can't head off in the opposite direction.
10. Modality / A. Necessity / 1. Types of Modality
Necessity is counterfactually implied by its negation; possibility does not counterfactually imply its negation
     Full Idea: Modal thinking is logically equivalent to a type of counterfactual thinking. ...The necessary is that which is counterfactually implied by its own negation; the possible is that which does not counterfactually imply its own negation.
     From: Timothy Williamson (Modal Logic within Counterfactual Logic [2010], 1)
     A reaction: I really like this, because it builds modality on ordinary imaginative thinking. He says you just need to grasp counterfactuals, and also negation and absurdity, and you can then understand necessity and possibility. We can all do that.
10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
Strict conditionals imply counterfactual conditionals: □(A⊃B)⊃(A□→B)
     Full Idea: The strict conditional implies the counterfactual conditional: □(A⊃B) ⊃ (A□→B) - suppose that A would not have held without B holding too; then if A had held, B would also have held.
     From: Timothy Williamson (Modal Logic within Counterfactual Logic [2010], 1)
     A reaction: [He then adds a reading of his formula in terms of possible worlds] This sounds rather close to modus ponens. If A implies B, and A is actually the case, what have you got? B!
10. Modality / B. Possibility / 9. Counterfactuals
Counterfactual conditionals transmit possibility: (A□→B)⊃(◊A⊃◊B)
     Full Idea: The counterfactual conditional transmits possibility: (A□→B) ⊃ (◊A⊃◊B). Suppose that if A had held, B would also have held; the if it is possible for A to hold, it is also possible for B to hold.
     From: Timothy Williamson (Modal Logic within Counterfactual Logic [2010], 1)
10. Modality / C. Sources of Modality / 1. Sources of Necessity
Rather than define counterfactuals using necessity, maybe necessity is a special case of counterfactuals
     Full Idea: Instead of regarding counterfactuals as conditionals restricted to a range of possible worlds, we can define the necessity operator by means of counterfactuals. Metaphysical necessity is a special case of ordinary counterfactual thinking.
     From: report of Timothy Williamson (Modal Logic within Counterfactual Logic [2010]) by Bob Hale/ Aviv Hoffmann - Introduction to 'Modality' 2
     A reaction: [compressed] I very much like Williamson's approach, of basing these things on the ordinary way that ordinary people think. To me it is a welcome inclusion of psychology into metaphysics, which has been out in the cold since Frege.
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
We can't infer metaphysical necessities to be a priori knowable - or indeed knowable in any way
     Full Idea: The inference from metaphysical necessity to a priori knowlability is, as Kripke has emphasized, fallacious. Indeed, metaphysical necessities cannot be assumed knowable in any way at all.
     From: Timothy Williamson (Vagueness [1994], 7.4)
     A reaction: The second sentence sounds like common sense. He cites Goldbach's Conjecture. A nice case of the procedural rule of keeping your ontology firmly separated from your epistemology. How is it? is not How do we know it?
Modal thinking isn't a special intuition; it is part of ordinary counterfactual thinking
     Full Idea: The epistemology of metaphysical modality requires no dedicated faculty of intuition. It is simply a special case of the epistemology of counterfactual thinking, a kind of thinking tightly integrated with our thinking about the spatio-temporal world.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], 5.6)
     A reaction: This seems to me to be spot-on, though it puts the focus increasingly on the faculty of imagination, as arguably an even more extraordinary feature of brains than the much-vaunted normal consciousness.
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
Williamson can't base metaphysical necessity on the psychology of causal counterfactuals
     Full Idea: The psychological mechanism that Williamson proposes as the supposedly reliable source of our knowledge of necessities only seems applicable to counterfactuals that are distinctively causal, not metaphysical, in character.
     From: comment on Timothy Williamson (The Philosophy of Philosophy [2007]) by E.J. Lowe - What is the Source of Knowledge of Modal Truths? 5
     A reaction: My rough impression of Williamson's account is that it is correct but unilluminating. We have to assess necessities by counterfactual thinking, because nothing else is available (apart from evaluating the coherence of the findings).
We scorn imagination as a test of possibility, forgetting its role in counterfactuals
     Full Idea: The epistemology of modality often focuses on (and pours scorn on) imagination or conceivability as a test of possibility, while ignoring the role of the imagination in the assessment of mundane counterfactuals.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], 5.4)
     A reaction: Good point. I've been guilty of this easy scorn myself. Williamson gives our modal capacities an evolutionary context. What is needed is well-informed imagination, rather than wild fantasy.
10. Modality / E. Possible worlds / 3. Transworld Objects / e. Possible Objects
Our ability to count objects across possibilities favours the Barcan formulas
     Full Idea: Consideration of our ability to count objects across possibilities strongly favour both the Barcan formula and its converse.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §3)
     A reaction: I'm not sure that I can understand counting objects across possibilities. The objects themselves are possibilia, and possibilia seem to include unknowns. The unexpected is highly possible.
If talking donkeys are possible, something exists which could be a talking donkey
     Full Idea: Williamson's view on modality is that everything that could exist does exist: since there could exist a talking donkey there actually exists some thing that could be a talking donkey.
     From: report of Timothy Williamson (Modal Logic as Metaphysics [2013], n20) by Ross P. Cameron - Truthmaking for Presentists n20
     A reaction: Well that thing certainly isn't me, or Tim Williamson. I'm guessing that the thing is an actual donkey, probably a rather bright one. Actually, I think this is one of those views that invites the incredulous stare. (Barcan formulae).
11. Knowledge Aims / A. Knowledge / 1. Knowledge
We have inexact knowledge when we include margins of error
     Full Idea: Inexact knowledge is a widespread and easily recognised cognitive phenomenon, whose underlying nature turns out to be characterised by the holding of margin of error principles.
     From: Timothy Williamson (Vagueness [1994], 8.3)
     A reaction: Williamson is invoking this as a tool in developing his epistemic view of vagueness. It obviously invites the question of how it can be knowledge if error is a possibility. A very large margin of error would obviously invalidate it.
11. Knowledge Aims / A. Knowledge / 4. Belief / c. Aim of beliefs
Belief aims at knowledge (rather than truth), and mere believing is a kind of botched knowing
     Full Idea: Knowing is the best kind of believing. Mere believing is a kind of botched knowing. In short, belief aims at knowledge (not just truth).
     From: Timothy Williamson (Knowledge and its Limits [2000], §1.5)
     A reaction: The difference between aiming at truth and aiming at knowledge has to be in the justificiation, so beliefs aim to be justified. Believers always aim at truth, but they can be strikingly relaxed about justification.
11. Knowledge Aims / A. Knowledge / 7. Knowledge First
Don't analyse knowledge; use knowledge to analyse other concepts in epistemology
     Full Idea: Williamson says that instead of being viewed as a concept to be analysed, knowledge should be seen as something useful in the analysis of all sorts of other concepts to epistemology - and to philosophy of mind as well.
     From: report of Timothy Williamson (Knowledge and its Limits [2000]) by Keith DeRose - The Case for Contextualism 1.8
     A reaction: I just don't believe this, because knowledge is obviously a complex state of mind, which invites breaking it down into ingredients. How could knowledge possibly be prior to truth?
We don't acquire evidence and then derive some knowledge, because evidence IS knowledge
     Full Idea: When we acquire new evidence in perception, we do not first acquire unknown evidence and then somehow base knowledge on it later. Rather, acquiring new is evidence IS acquiring new knowledge.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.4)
     A reaction: This makes his point much better than Idea 19526 does.
Knowledge is prior to believing, just as doing is prior to trying to do
     Full Idea: Knowing corresponds to doing, believing to trying. Just as trying is naturally understood in relation to doing, so believing is naturally understood in relation to knowing.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.4)
     A reaction: An interesting analogy. You might infer that there can be no concept of 'belief' without the concept of 'knowledge', but we could say that it is 'truth' which is indispensible, and leave out knowledge entirely. Belief is to truth as trying is to doing?
Belief explains justification, and knowledge explains belief, so knowledge explains justification
     Full Idea: If justification is the fundamental epistemic norm of belief, and a belief ought to constitute knowledge, then justification should be understood in terms of knowledge too.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.5)
     A reaction: If we are looking for the primitive norm which motivates the whole epistemic game, then I am thinking that truth might well play that role better than knowledge. TW would have to reply that it is the 'grasped truth', rather than the 'theoretical truth'.
A neutral state of experience, between error and knowledge, is not basic; the successful state is basic
     Full Idea: A neutral state covering both perceiving and misperceiving (or remembering and misrembering) is not somehow more basic than perceiving, for what unifies the case of each neutral state is their relation to the successful state.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.5-6)
     A reaction: An alternative is Disjunctivism, which denies the existence of a single neutral state, so that there is nothing to unite the two states, and they don't have a dependence relation. Why can't there be a prior family of appearances, some of them successful?
Internalism about mind is an obsolete view, and knowledge-first epistemology develops externalism
     Full Idea: A postulated underlying layer of narrow mental states is a myth, whose plausibility derives from a comfortingly familiar but obsolescent philosophy of mind. Knowledge-first epistemology is a further step in the development of externalism.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.6)
     A reaction: Williamson is a real bruiser, isn't he? I don't take internalism about mind to be obsolescent at all, but now I feel so inferior for clinging to such an 'obsolescent' belief. ...But then I cling to Aristotle, who is (no doubt) an obsolete philosopher.
Knowledge-first says your total evidence IS your knowledge
     Full Idea: Knowledge-first equate one's total evidence with one's total knowledge.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.8)
     A reaction: Couldn't lots of evidence which merely had a high probability be combined together to give a state we would call 'knowledge'? Many dubious witnesses confirm the truth, as long as they are independent, and agree.
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / b. Direct realism
Surely I am acquainted with physical objects, not with appearances?
     Full Idea: When I ask myself what I am acquainted with, the physical objects in front of me are far more natural candidates than their appearances.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.3)
     A reaction: Not very impressive. The word 'acquainted' means the content of the experience, not the phenomena. Do I 'experience' the objects, or the appearances? The answer there is less obvious. If you apply it to colours, it is even less obvious.
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
There are 'armchair' truths which are not a priori, because experience was involved
     Full Idea: There is extensive 'armchair knowledge' in which experience plays no strictly evidential role, but it may not fit the stereotype of the a priori, because the contribution of experience was more than enabling, such as armchair truths about our environment.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], 5.5)
     A reaction: Once this point is conceded we have no idea where to draw the line. Does 'if it is red it can't be green' derive from experience? I think it might.
12. Knowledge Sources / B. Perception / 1. Perception
How can one discriminate yellow from red, but not the colours in between?
     Full Idea: If one takes a spectrum of colours from yellow to red, it might be that given a series of colour samples along that spectrum, each sample is indiscriminable by the naked eye from the next one, though samples at either end are blatantly different.
     From: Timothy Williamson (Interview with Baggini and Stangroom [2001], p.151)
     A reaction: This seems like a nice variant of the Sorites paradox (Idea 6008). One could demonstrate it with just three samples, where A and C seemed different from each other, but other comparisons didn't.
12. Knowledge Sources / E. Direct Knowledge / 2. Intuition
Intuition is neither powerful nor vacuous, but reveals linguistic or conceptual competence
     Full Idea: Crude rationalists postulate a special knowledge-generating faculty of rational intuition. Crude empiricists regard intuition as an obscurantist term of folk psychology. Linguistic/conceptual philosophy says it reveals linguistic or conceptual competence.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], Intro)
     A reaction: Kripke seems to think that it is the basis of logical competence. I would use it as a blank term for any insight in which we have considerable confidence, and yet are unable to articulate its basis; roughly, for rational thought that evades logic.
When analytic philosophers run out of arguments, they present intuitions as their evidence
     Full Idea: 'Intuition' plays a major role in contemporary analytic philosophy's self-understanding. ...When contemporary analytic philosophers run out of arguments, they appeal to intuitions. ...Thus intuitions are presented as our evidence in philosophy.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], p.214-5), quoted by Herman Cappelen - Philosophy without Intuitions 01.1
     A reaction: Williamson says we must investigate this 'scandal', but Cappelen's book says analytic philosophy does not rely on intuition.
13. Knowledge Criteria / A. Justification Problems / 1. Justification / a. Justification issues
Knowing you know (KK) is usually denied if the knowledge concept is missing, or not considered
     Full Idea: The failure of the KK principle is not news. The standard counterexamples involve knowing subjects who lack the concept of knowledge, or have not reflected on their knowledge, and therefore do not know that they know.
     From: Timothy Williamson (Vagueness [1994], 8.2)
     A reaction: There is also the timid but knowledgeable pupil, who can't believe they know so much. The simplest case would be if we accept that animals know lots of things, but are largely devoid of any metathinking.
15. Nature of Minds / C. Capacities of Minds / 2. Imagination
Imagination is important, in evaluating possibility and necessity, via counterfactuals
     Full Idea: Imagination can be made to look cognitively worthless. Once we recall its fallible but vital role in evaluating counterfactual conditionals, we should be more open to the idea that it plays such a role in evaluating claims of possibility and necessity.
     From: Timothy Williamson (Modal Logic within Counterfactual Logic [2010], 6)
     A reaction: I take this to be a really important idea, because it establishes the importance of imagination within the formal framework of modern analytic philosopher (rather than in the whimsy of poets and dreamers).
18. Thought / A. Modes of Thought / 2. Propositional Attitudes
To know, believe, hope or fear, one must grasp the thought, but not when you fail to do them
     Full Idea: To know, believe, hope, or fear that A, one must grasp the thought that A. In contrast, to fail to know, believe, hope or fear that A, one need not grasp the thought that A.
     From: Timothy Williamson (Vagueness [1994], 9.3 c)
     A reaction: A simple point, which at least shows that propositional attitudes are a two-stage operation.
18. Thought / D. Concepts / 4. Structure of Concepts / h. Family resemblance
'Blue' is not a family resemblance, because all the blues resemble in some respect
     Full Idea: 'Blue' is vague by some standards, for it has borderline cases, but that does not make it a family resemblance term, for all the shades of blue resemble each other in some respect.
     From: Timothy Williamson (Vagueness [1994], 3.3)
     A reaction: Presumably the point of family resemblance is that fringe members as still linked to the family, despite having lost the main features. A bit of essentialism seems needed here.
19. Language / A. Nature of Meaning / 6. Meaning as Use
You might know that the word 'gob' meant 'mouth', but not be competent to use it
     Full Idea: Someone who acquires the word 'gob' just by being reliably told that it is synonymous with 'mouth' knows what 'gob' means without being fully competent to use it.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], 4.7)
     A reaction: Not exactly an argument against meaning-as-use, but a very nice cautionary example to show that 'knowing the meaning' of a word may be a rather limited, and dangerous, achievement.
19. Language / B. Reference / 1. Reference theories
References to the 'greatest prime number' have no reference, but are meaningful
     Full Idea: The predicate 'is a prime number greater than all other prime numbers' is necessarily not true of anything, but it is not semantically defective, for it occurs in sentences that constitute a sound proof that there is no such number.
     From: Timothy Williamson (Vagueness [1994], 6.2)
     A reaction: One might reply that the description can be legitimately mentioned, but not legitimately used.
19. Language / C. Assigning Meanings / 2. Semantics
The 't' and 'f' of formal semantics has no philosophical interest, and may not refer to true and false
     Full Idea: In a formal semantics we can label two properties 't' and 'f' and suppose that some sentences have neither (or both). Such a manoeuvre shows nothing of philosophical interest. No connection has been made between 't' and 'f' and truth and falsity.
     From: Timothy Williamson (Vagueness [1994], 7.2)
     A reaction: This is right, and means there is a huge gulf between 'formal' semantics (which could be implemented on a computer), and seriously interesting semantics about how language refers to and describes the world.
How does inferentialism distinguish the patterns of inference that are essential to meaning?
     Full Idea: Inferentialism faces the grave problem of separating patterns of inference that are to count as essential to the meaning of an expression from those that will count as accidental (a form of the analytic/synthetic distinction).
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.6)
     A reaction: This sounds like a rather persuasive objection to inferentialism, though I don't personally take that as a huge objection to all internalist semantics.
Internalist inferentialism has trouble explaining how meaning and reference relate
     Full Idea: The internalist version of inferentialist semantics has particular difficulty in establishing an adequate relation between meaning and reference.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.6)
     A reaction: I would have thought that this was a big problem for referentialist semantics too, though evidently Williamson doesn't think so. If he is saying that the meaning is in the external world, dream on.
Inferentialist semantics relies on internal inference relations, not on external references
     Full Idea: On internalist inferential (or conceptual role) semantics, the inferential relations of an expression do not depend on what, if anything, it refers to, ...rather, the meaning is something like its place in a web of inferential relations.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.6)
     A reaction: Williamson says the competition is between externalist truth-conditional referential semantics (which he favours), and this internalist inferential semantics. He is, like, an expert, of course, but I doubt whether that is the only internalist option.
19. Language / C. Assigning Meanings / 7. Extensional Semantics
Truth-conditional referential semantics is externalist, referring to worldly items
     Full Idea: Truth-conditional referential semantics is an externalist programme. In a context of utterance the atomic expressions of a language refer to worldly items, from which the truth-conditions of sentences are compositionally determined.
     From: Timothy Williamson (Knowledge First (and reply) [2014], p.6)
     A reaction: I just don't see how a physical object can be part of the contents of a sentence. 'Dragons fly' is atomic, and meaningful, but its reference fails. 'The cat is asleep' is just words - it doesn't contain a live animal.
19. Language / D. Propositions / 2. Abstract Propositions / b. Propositions as possible worlds
It is known that there is a cognitive loss in identifying propositions with possible worlds
     Full Idea: It is well known that when a proposition is identified with the set of possible worlds at which it is true, a region in the space of possible worlds, cognitively significant distinctions are lost.
     From: Timothy Williamson (Vagueness [1994], 7.6)
     A reaction: Alas, he doesn't specify which distinctions get lost, so this is just a pointer. It would seem likely that two propositions could have identical sets of possible worlds, while not actually saying the same thing. Equilateral/equiangular.
19. Language / D. Propositions / 3. Concrete Propositions
Propositions (such as 'that dog is barking') only exist if their items exist
     Full Idea: A proposition about an item exists only if that item exists... how could something be the proposition that that dog is barking in circumstances in which that dog does not exist?
     From: Timothy Williamson (Necessary Existents [2002], p.240), quoted by Trenton Merricks - Propositions
     A reaction: This is a view of propositions I can't make sense of. If I'm under an illusion that there is a dog barking nearby, when there isn't one, can I not say 'that dog is barking'? If I haven't expressed a proposition, what have I done?
24. Political Theory / B. Nature of a State / 5. Culture
If languages are intertranslatable, and cognition is innate, then cultures are all similar
     Full Idea: Given empirical evidence for the approximate intertranslatability of all human languages, and a universal innate basis of human cognition, we may wonder how 'other' any human culture really is.
     From: Timothy Williamson (The Philosophy of Philosophy [2007], 8.1)
     A reaction: This seems to be a fairly accurate account of the situation. In recent centuries people seem to have been over-impressed by superficial differences in cultural behaviour, but we increasingly see the underlying identity.
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
A thing can't be the only necessary existent, because its singleton set would be as well
     Full Idea: That there is just one necessary existent is surely false, for if x is a necessary, {x} is a distinct necessary existent.
     From: Timothy Williamson (Truthmakers and Converse Barcan Formula [1999], §1)
     A reaction: You would have to believe that sets actually 'exist' to accept this, but it is a very neat point.