Letter of the month

David Lewis’s typewriter.

The Letter of the month series ran from November 2016 to May 2019.

Scroll the entries below to see the wide variety of letters that we posted throughout the course of the project. You’ll be able to see the original letter along with some scene-setting and discussion of some of the issues it raises.

Many of these letters are now published in the two-volume Philosophical Letters of David K. Lewis.

Letter of the Month, last one!

David Lewis published a seminal paper on time travel in 1976, called 'The Paradoxes of Time Travel'. It is a foundational piece that has impacted later discussions of time travel in analytic metaphysics. The paper was read at the APA in March 1976. His commentator was...

Letter of the Month, May 2019

David Lewis was a contented atheist. He was adamant that he would never be converted. Throughout his career as he discussed topics of religion with other philosophers he realised that he would never convert his opponents either. Despite this, he thought there was...

Letter of the Month, April 2019

This month’s letter — from Lewis to Tony Coady — is a bit of light relief from abstract philosophising. Lewis is worrying about testimony, and in particular worrying about whether or to what extent someone’s known past deception affects, or should affect, whether we...

Letter of the Month, March 2019

Letter of the Month, March 2019

March’s letter of the month concerns the general problem of scepticism. In ‘Elusive Knowledge’ Lewis came be seen as answering the sceptic by explaining in what ways we can know certain things. But he also presented a theory about how our knowledge of certain things...

Letter of the Month, February 2019

In February’s letter of the month, Lewis responds to Stewart Cohen’s 1998 article ‘Contextualist Solutions to Epistemological Problems: Scepticism, Gettier, and the Lottery’, Australasian Journal of Philosophy 76 (2):289 – 306. Lewis accepts the suggestion that the...

Letter of the Month, January 2019

One area of philosophy that Lewis had an impact on was epistemology. But, unlike other areas he influenced, his writings on epistemology derive from just one article, namely, his widely read 1996 'Elusive Knowledge', Australasian Journal of Philosophy vol. 74. It is...

Letter of the Month, December 2018

December’s letter of the month is to Paul Fitzgerald, a peer of David Lewis at Harvard University who wrote his thesis on the metaphysics of time under Donald C. Williams. This letter is in reaction to Fitzgerald’s The Truth About Tomorrow's Sea Fight. 1969. Journal...

Letter of the month, November 2018

Lewis and Vagueness (guest post, by Daniel Nolan, University of Notre Dame) This month's letter is an eleven-page letter David Lewis sent to Timothy Williamson in May 1999. The letter divides into three main sections. In the first, Lewis sets out his own views about...

Letter of the month, October 2018

Letter of the month, October 2018

‘Truth in Fiction’ is a celebrated paper in the analytic tradition on the nature and function of fiction. Lewis published the paper in the American Philosophical Quarterly in 1978 (vol. 15). But, as his correspondence reveals, the gist of his theory of fiction...

Letter of the month, September 2018

In ‘New Work for a Theory of Universals’ and ‘Putnam’s Paradox’ Lewis famously argued that Putnam’s model-theoretic argument against realism fails. His response to Putnam is that there is a real division between natural and non-natural properties out there in the...

Letter of the month, August 2018

Soon after the publication of Gareth Evans’s classic one-page Analysis paper on vagueness in 1978, Lewis was struck by how many misunderstood what Evans was up to. He wrote several letters about this issue. His letter to Allen Hazen, 15 November 1978, led to Lewis’s...

Letter of the month, July 2018

Lewis’s recipient - John Coker - was a student of Alvin Plantinga at Notre Dame in the 1980s. Coker wrote a paper arguing that modal realism, with Lewis’s added trappings of concrete worlds, no overlap, qualified principle of recombination, etc, is atheististic in the...

Letter of the month, June 2018

In this letter, Lewis provides comments on a draft of Colin McGinn’s 1980 Functionalism and Phenomenalism: A Critical Note. Australasian Journal of Philosophy 58 (March):35-46. This letter is important for understanding Lewis’s theory of mind but also for...

Letter of the month, May 2018

Letter of the month, May 2018

In this letter to Campbell, Lewis discusses the relationship between tropes and theories of space and time in the philosophy of physics. What is a Trope? Tropes are properties or relations which are not universal, but particular. For instance, the blackness of this...

Letter of the month, April 2018

In this letter to Solomon, Lewis reflects on disagreement in philosophy and ascribing mental states to turkeys. Disagreement in Logic and Philosophy Lewis believes that philosophical disagreements often reach a deadlock where neither side will move. Lewis here points...

Letter of the month, March 2018

In this letter to Follesdal, Lewis presents an early draft of his famous theory of counterparts. Do Possible Worlds Exist? Famously, Lewis believed in the existence of infinitely many physical possible universes. Lewis had been an early adopter of modal logic. Such...

Letter of the Month, July 2017

This month's letter is from 1984 and sees Lewis asking the cartoonist Roz Chast whether she will allow him to use her 'Parallel Universes' cartoon as the frontispiece for On the Plurality of Worlds. Chast said 'no' since she was about to use it as the cover for her...

Letter of the Month, June 2017

Letter of the Month, June 2017

June’s letter of the month concerns various connections between modal logic and ordinary language. Does modal logic have its own source of intuitions? Is modal logic or ‘modal language’ as philosophers conceive of it a thing of its own? What is it exactly? In this...