Timothy Williamson FRSE FBA
Williamson in 2014
Born	(1955-08-06)6 August 1955 (age 70) Uppsala,Sweden
Academic background
Alma mater	Balliol College, Oxford
Thesis	The Concept of Approximation to the Truth (1980)
Influences	Ruth Barcan Marcus
Academic work
Era	Contemporary philosophy
Discipline	Philosophy
Sub-discipline	Epistemology logic metaphysics philosophy of language
School or tradition	Analytic philosophy
Institutions	Trinity College, Dublin University College, Oxford University of Edinburgh New College, Oxford
Doctoral students	Maria Baghramian Amia Srinivasan
Main interests	Epistemology,metaphysics,vagueness
Notable ideas	Epistemicism knowledge as conceptually primitive knowledge-first epistemology modal logic asmetaphysics
Influenced	John Hawthorne Jason Stanley

Timothy Williamson (born 6 August 1955) is a Britishphilosopher whose main research interests are inphilosophical logic,philosophy of language,epistemology andmetaphysics. He is the formerWykeham Professor of Logic at theUniversity of Oxford, and a fellow ofNew College, Oxford.

Born on 6 August 1955, Williamson's education began atLeighton Park School and continued at Henley Grammar School (nowthe Henley College).^{[citation needed]} He then went toBalliol College,Oxford University. He graduated in 1976 with aBachelor of Arts degree withfirst-class honours in mathematics and philosophy, and in 1980 with a doctorate in philosophy (DPhil) for a thesis entitledThe Concept of Approximation to the Truth.^[1]

Williamson was professor of logic and metaphysics at theUniversity of Edinburgh (1995–2000), fellow and lecturer in philosophy atUniversity College, Oxford (1988–1994), and lecturer in philosophy atTrinity College, Dublin (1980–1988). He took up the Wykeham Professorship in 2000 and retired in 2023, when he took up a Senior Research and Teaching Fellowship in Philosophy.^[2]

He has been visiting professor atYale University,Princeton University,MIT, theUniversity of Michigan, and theChinese University of Hong Kong.

He was president of theAristotelian Society from 2004 to 2005.

He is aFellow of the British Academy (FBA),^[3] theNorwegian Academy of Science and Letters,^[4]Fellow of the Royal Society of Edinburgh (FRSE), and a Foreign Honorary Fellow of theAmerican Academy of Arts & Sciences.

Since 2022 he is visiting professor at theUniversità della Svizzera Italiana.

Williamson has contributed toanalyticphilosophy of language,logic,metaphysics,epistemology,metaethics andmetaphilosophy.

Onvagueness, he holds a position known asepistemicism, which states that every seemingly vaguepredicate (like "bald" or "thin") actually has a sharp cutoff, which is impossible for us to know.^[5] For instance, there is some number of hairs such that anyone with that number is bald, and anyone with even one more hair is not. In actuality, this condition will be spelled out only partly in terms of numbers of hairs, but whatever measures are relevant will have some sharp cutoff. This solution to the difficultSorites paradox was considered a surprising and unacceptable consequence, but has become a relatively mainstream view since his defence of it.^[6] Williamson is fond of using the statement, "no one knows whether I am thin" to illustrate his view.^[7]

Inepistemology, Williamson suggests thatknowledge is unanalysable. This went against the common trend in philosophical literature up to that point, which was to argue that knowledge could be analysed into constituent concepts. (Typically, this would bejustified true belief plus an extra factor.) He agrees that knowledge entails justification, truth andbelief, but argues that it is conceptually primitive. He accounts for the importance of belief by discussing its connections with knowledge, but avoids the disjunctivist position of saying that belief can be analysed as the disjunction of knowledge with some distinct, non-factive mental state.^[8]

Williamson also argues against the traditional distinction ofknowing-how andknowing-that. He claims that knowledge-how is a type of knowledge-that. Williamson argues that knowledge-how does not relate one's ability. He provides the example of a ski instructor who knows how to perform a complex move without having the ability to do it himself.^[9]

Inmetaphysics, Williamson defends necessitism, according to which necessarily everything is necessarily something; in short, that everything exists of necessity.^[10] Likewise, it is possible for something to have a property only if there is something which has that property. For instance, since it is possible forWittgenstein to have had a child, there is something which is a possible child of Wittgenstein. Necessitism is a theoretical interpretation of theBarcan formula, which is a theorem of themodal logic S5. However, Williamson has also developed an ontology of “bare possibilia” which he argues accounts for the seemingly unintuitive consequences of necessitism.^[11]

• Identity and Discrimination, Oxford: Blackwell, 1990.
• Vagueness, London:Routledge, 1994.
• Knowledge and Its Limits, Oxford: Oxford University Press, 2000.
• The Philosophy of Philosophy, Oxford: Blackwell, 2007
  • The Philosophy of Philosophy (2nd ed.), Hoboken: Wiley Blackwell, 2022.
• Modal Logic as Metaphysics, Oxford: Oxford University Press, 2013.
• Tetralogue: I'm Right, You're Wrong, Oxford: Oxford University Press, 2015.
• Doing Philosophy: From Common Curiosity to Logical Reasoning, Oxford University Press, 2017.
• Suppose and Tell: The Semantics and Heuristics of Conditionals, Oxford University Press, 2020.
• Debating the A Priori (withPaul Boghossian), Oxford University Press, 2020.
• Overfitting and Heuristics in Philosophy, Oxford University Press, 2024.
• Good as Usual: Anti-Exceptionalist Essays on Values, Norms and Actions, Oxford University Press, 2025.

Williamson has also published more than 120 articles in peer-reviewed scholarly journals.

• Profile at University of Oxford
• An in-depth autobiographical interview with Timothy Williamson at What Is It Like to Be a Philosopher?
• Interview at3:AM Magazine
• Università della Svizzera Italiana professors.

• 1955 births
• Living people
• 20th-century British philosophers
• 21st-century British philosophers
• Academics of the University of Edinburgh
• Analytic philosophers
• Philosophers of language
• British philosophers of mind
• Metaphysicians
• Fellows of New College, Oxford
• Fellows of the British Academy
• Fellows of the Royal Society of Edinburgh
• Fellows of University College, Oxford
• Academics of Trinity College Dublin
• Wykeham Professors of Logic
• Members of the Norwegian Academy of Science and Letters
• People from Uppsala
• Atheist philosophers
• Presidents of the Aristotelian Society
• British social philosophers
• Henry Wilde Prize winners

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