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From time to time, I receive email that might be of interest to Lawrentians. Here is a selection.

Posted October 17, 2006

The Interlocutor: Sewanee Philosophical Review/ is pleased to announce its most recent volume and a call for high quality undergraduate essays for its upcoming volume.

Please send this announcement to students who might have an interest in this opportunity.

Our call for essays and instructions for submissions can be viewed at

The most recent volume is available at

If you or your students have questions, please feel free to contact me.

Jim Peterman
Professor and Chair, Philosophy
The University of the South
735 University Avenue
Sewanee, TN 37375

931-598-1482 (w)
931-598-0457 (h)

Posted October 17, 2006

Truth and Reality

Hosted by the Philosophy Department, University of Otago, Dunedin, New Zealand

8-12 January 2007

Keynote Speakers

Michael Devitt (CUNY)
D. H. Mellor (Cambridge)
John Heil (Washington University at St Louis)

Confirmed speakers
JC Beall (Connecticut), David Chalmers (ANU), Mark Colyvan (Sydney), John Fox (La Trobe), Frank Jackson (ANU), Fred Kroon (Auckland), Robert Nola (Auckland), Greg Restall (Melbourne), J.J.C. Smart (Monash), Michael Smith (Princeton), Paul Snowdon (UCL), Dan Stoljar (ANU), Jamie Whyte (Author of Crimes Against Logic)

Questions about the nature of truth are as old as philosophy itself.
Recently, however, there has been a resurgence of interest in issues surrounding the relationship between truth and the world. What is truth? On the one hand, it seems obvious that it is something that applies to the things we think and say. Many of our beliefs about the world, and sentences describing it are, we think, true. On the other hand, it seems intimately connected with the world we think and speak about, for it is in virtue of the way the world is that many of our sentences and beliefs are true. This conference will investigate this relationship between truth and reality. Some of the topics covered may include: truthmakers, realism and anti-realism, correspondence theories of truth, deflationism and truth in ethics.

The conference will be a tribute to Professor Alan Musgrave, who has led the Otago Philosophy Department for the last 36 years. Alan has been a significant contributor to the philosophical literature on the issues which form the focus of this conference.

Venue: Burns Building, University of Otago

The registration form is available to download from the conference website (

Further information regarding the conference programme and accommodation will be posted on the website shortly.

Conference organiser: Heather Dyke (

About the Location

Dunedin is situated on the beautiful South Island of New Zealand approximately 360km south of Christchurch. It is a 3-4 hour drive from the lakes, mountains and vineyards of Central Otago. January is mid-summer in New Zealand, so the conference will offer Northern Hemisphere philosophers a welcome respite from the rigours of their winter. For more information visit the following websites:

Dr Heather Dyke, Department of Philosophy, University of Otago, P.O Box 56, Dunedin, New Zealand

Tel: +64-3-479 8727
Fax: +64-3-479 5035

Posted January 20, 2006

This Week on the Guerrilla Radio Show! (Tuesday, 01.17.06)
Live Webcast- GMT 12:00 am on Wednesday, 01.18.06

Philosophy of Science 101
What is the philosophy of science? What is it that philosophers of science do? What sort of issues is the philosophy of science interested in investigating? What is the relationship between science and the philosophy of science? How do philosophers add to the work of scientists? Do scientists need philosophers of science? Can the structure and history of science tell us anything about how to do philosophy? What scientific fields ought to be studied more by philosophers of science? Be sure and join the GRS crew and special guest Christopher Smeenk, Ph.D. (University of California, Los Angeles) for this important discussion!  


The GRS airs on Tuesday nights 7:00-8:00 PM (PST) on KCSB 91.9 FM (Santa Barbara, CA) or Live on the World Wide Web (via web-cast) at

On Air Calls: 1 (805) 893-2424
Email comments:
GRS Website:
GRS PodCast Channel:



Dear Philosophy Enthusiasts,  There’s a brand new philosophy talk show assaulting the radio airwaves!  The Guerrilla Radio Show is the only Cutting Edge Philosophy Talk Show of its kind. Just imagine the humor and wit of John Stewart’s Daily Show or HBO’s Real Time with Bill Maher combined with the informative content of 60 Minutes or CNN’s Crossfire. Now imagine a show that debates and discusses foundational issues (e.g. What is real?  What is knowledge? How should we determine right and wrong? etc.) with logical clarity and keen philosophical acumen. Welcome to the Guerrilla Radio Show!

Committed to Waging War Against Idiocy and Bringing Philosophy to the Masses, the Guerrilla Radio Show offers listeners a fresh, no-nonsense perspective on life and the world we live in. The show is educational, exciting, cutting-edge and jam-packed with controversial issues, expert guest opinions, live caller interviews and enough wit and sarcasm to kill a horse! With a format like that, the Guerrilla Radio Show is sure to make a forceful impact on the fragile radio airwaves of America.

The Guerrilla Radio Show is unique, informative and wildly entertaining. A philosophy talk show doesn’t have to be stuffy, boring or incapable of attracting younger audiences. Cool music, controversial topics and hilarious hosts make the Guerrilla Radio Show one of the hottest tickets this year... its Philosophy with a Sense of Humor.  If you’re interested in philosophy, you can’t afford to miss this the Guerrilla Radio Show!

The Guerrilla Radio Show can be heard live on KCSB 91.9 FM (Los Angeles to Sacramento) or via World Wide Web-cast ( every Tuesday night from 7:00-8:00 PM (Pacific Standard Time). You can also listen to archived episodes of the show by logging on to the Guerrilla Radio Show’s website @

Posted November 18, 2005

The Interlocutor: Sewanee Philosophical Review is pleased to announce its most recent volume and a call for high quality undergraduate essays for its upcoming volume. 

Please send this announcement to students who might have an interest in this opportunity.

Our call for essays and instructions for submissions can be viewed at

The most recent volumes is available at

If you or your students have questions, please feel free to contact me.

Jim Peterman

Posted September 14, 2005

Submit to the Yale Philosophy Review: An Undergraduate Publication!
The Yale Philosophy Review is a bi-annual undergraduate journal at Yale University that showcases the best and most original of philosophic thought by undergraduate students, worldwide. The goal of the Review is to promote philosophic discourse of the highest standard, and to bring together a community of young philosophers in both the United States and abroad. Each issue contains a selection of essays on a broad range of philosophic topics, as well as book reviews and interviews of philosophic content.

For those who are university professors or graduate students, please pass this information on to your undergraduate students! For those who are undergraduates, you can send submissions as attached email files to this address or to

Please visit our website!


Book Reviews and Interviews Submission. If you are interested in writing a book review or an interview for The Yale Philosophy Review, please email the editors with a proposed book (published within the last twelve months) or interviewee. Final publication of book reviews and interviews is at the discretion of the Editors.

Paper and Essay Submission. Papers should be 10-20 double-spaced pages in MLA format. Papers must be the original work of the author, with all sources and references properly cited.

While we do not take previously published papers, we do accept simultaneous submissions, with the expectation that we will be informed immediately if the paper is being published elsewhere.

Please include a cover page with the following information: Name, University or College, Major or Degree, Year of expected graduation, Email, Phone number, and Address. Do not include any personal information on the paper itself. Please include a short (500 word max.) abstract at the beginning of your paper.

Deadline and Submission Information. All submissions for the Spring 2005 issue must be postmarked or emailed by February 1, 2006.

By Mail:
Yale Philosophy Review
109 Church St. #309
New Haven, CT, 06510, USA.

By Email:
Please send your submission as a Microsoft Word or Adobe PDF formatted attachment to
Questions? Email the Editors at


Posted June 3, 2005:

The British Undergraduate Philosophy Society is launching a new online philosophy discussion group - Provocations Online - and all undergraduate-level philosophers are invited to join in.

Provocations Online will offer two new topics every month for open debate via our email discussion list BUPS-DIS. This month's discussions will be

- The Status of Jacques Derrida's Philosophy
- The Incompatibility of Determinism and Responsibility

The format of the discussion is simple. The current 'provoker' will:

- Name the topic or question they are particularly interested in
- Provide a brief summary of the different positions in the debate
- Give their own view on the subject

The topic is then open for discussion and reply by all list members.
Discussion will continue as long as people feel they have something to add, and a new topic will be introduced every fortnight.

The first provocation starts in a few days - why not swing by our website and sign up to catch the action? If you know anyone who might also enjoy our online discussions, please let them know!

All undergrad-level philosophers welcome!

Details of June Discussions:

Starting Wed 8th June: 'The status of Jacques Derrida's Philosophy' - Andrew Stephenson (Cardiff University)

'Derrida has repeatedly been named (against his own explicit wishes) as the founder and foremost practitioner of deconstruction - a continental school of philosophy with American (and therefore analytic) truncations that focuses on the close readings of texts, highlighting problems with language and logic (such as metaphor and bivalence respectively), authorial intent, and ultimately with all aspects of binary oppositions (subject/object, present/absent, inside/outside etc.). With his prolific output, Derrida has been loved and reviled, but whatever your relationship with him, he was one of the most important, challenging, interesting and rewarding figures of the history of Western philosophy.'

Starting Wed 22nd June: 'The Incompatibility of Determinism and Responsibility' - Robert Charleston (Open University)

'Intuitively it seems that moral responsibility and determinism must clash. If there are things - genetic programming, cultural attitudes, physical events - which cause us to act in a certain way, it seems we did not choose that act. To hold somebody morally responsible for something they did not choose seems unreasonable. So it seems that determinism - the idea that all events have such causes - must deny that we can be morally responsible for anything we do. But can this intuitive problem be resolved philosophically? Can determinism and responsibility be reconciled? Can indeterminism deliver responsibility any better than determinism? Are we perhaps looking at these terms in the wrong way?'

If you would like to be a provoker in July or August, please drop us a line at:

If you would like to know more about the British Undergraduate Philosophy Society, please visit our website:

See you on the list!

The BUPS Committee.


Paul Edwards (1923 – 2004)

Dr. Paul Edwards died at his expansive Apthorpe Apartments, 79th Street and Broadway, Manhattan, some time between 8:30 pm on Wednesday (8 Dec 2004) and Thursday (9 Dec 2004), according to an e-mail from his aide Alek Shlahet to Tim Madigan.

On Friday, the book-filled apartment of the editor of The Encyclopedia of Philosophy and recent member of the New School University faculty was sealed by the police. The body was removed to the coroner's office, it is to be cremated, and eventually friends will be invited to a ceremony at which the cremains will be thrown, as was his wish, into the Hudson River.

Tim Madigan and I upon several occasions visited Paul, and during the Thanksgiving weekend Tim had a long conversation with him, one that always ended with a scrambled eggs meal at a diner within walking distance.
Paul had complained about his health for decades, and during the last year or so his teeth gave him big problems.

Alek has assured us that he has complete files on Paul's "almost complete" (Paul's words) final book, one probably to be titled God and the Philosophers. Tim has helped in the past and both of us have seen the boxes filled with chapters of material.

As of Sunday, 12 Dec 2004), no obituaries have appeared, possibly because The New York Times staff has been unable to locate the executor of the estate. That staff, however, has been supplied by us with the executor's name. Unfortunately, photographs have always been difficult to find because Paul disliked being photographed. I took one photo surreptitiously one day several years ago in his Intro to Philosophy course at New School University.

Paul was a proud member of FANNY (Freethinking Activist Non-believing New Yorkers).

For further details, and a rare photo of Paul, see

Warren Allen Smith

Philosopher Nozick dies at 63

University professor was major intellectual figure of 20th century

By Ken Gewertz
Gazette Staff
Robert Nozick
Professor Robert Nozick

University Professor Robert Nozick, one of the late 20th century's most influential thinkers, died on the morning of Jan. 23 at the age of 63. He had been diagnosed with stomach cancer in 1994.

Nozick, known for his wide-ranging intellect and engaging style as both writer and teacher, had taught a course on the Russian Revolution during the fall semester and was planning to teach again in the spring. His last major book, "Invariances: The Structure of the Objective World," was published by Harvard University Press in October 2001.

According to Alan Dershowitz, the Felix Frankfurter Professor of Law and a longtime friend, Nozick had been talking with colleagues and critiquing their work until a week before his death.

"His mind remained brilliant and sharp to the very end," Dershowitz said.

He added that Nozick was "constantly probing, always learning new subjects. He was a University Professor in the best sense of the term. He taught everybody in every discipline. He was a wonderful teacher, constantly rethinking his own views and sharing his new ideas with students and colleagues. His unique philosophy has influenced generations of readers and will continue to influence people for generations to come."

Harvard President Lawrence H. Summers said of Nozick's passing, "I was deeply saddened to learn of the death of Robert Nozick. Harvard and the entire world of ideas have lost a brilliant and provocative scholar, profoundly influential within his own field of philosophy and well beyond. All of us will greatly miss his lively mind and spirited presence, but his ideas and example will continue to enrich us for years to come."

Dean of the Faculty of Arts and Sciences Jeremy R. Knowles said, "Bob Nozick was a luminous and wide-ranging philosopher who engaged students and colleagues from across the University and beyond. The loss to philosophy and to Harvard is grievous."

Philosophy Department Chair Christine Korsgaard described Nozick as "a brilliant and fearless thinker, very fast on his feet in discussion, and apparently interested in everything. Both in his teaching and in his writing, he did not stay within the confines of any traditional field, but rather followed his interests into many areas of philosophy. His works throw light on a broad range of philosophical issues, and on their connection with other disciplines. The courage with which he faced the last years of illness, and the irrepressible energy with which he continued to work, made a very deep impression on all of us."

Nozick's controversial and challenging views gained him considerable attention and influence in the world beyond the academy.

His first book, "Anarchy, State, and Utopia" (1974), transformed him from a young philosophy professor known only within his profession to the reluctant theoretician of a national political movement.

He wrote the book as a critique of "Theory of Justice" (1971), by his Harvard colleague John Rawls, the James Bryant Conant University Professor Emeritus. Rawls' book provided a philosophical underpinning for the bureaucratic welfare state, a methodically reasoned argument for why it was right for the state to redistribute wealth in order to help the poor and disadvantaged.

Nozick's book argued that the rights of the individual are primary and that nothing more than a minimal state - sufficient to protect against violence and theft, and to ensure the enforcement of contracts - is justified. "Anarchy, State, and Utopia" won the National Book Award and was named by The Times Literary Supplement as one of "The Hundred Most Influential Books Since the War."

A former member of the radical left who was converted to a libertarian perspective as a graduate student, largely through his reading of conservative economists Friedrich Hayek and Milton Friedman, Nozick was never comfortable with his putative status as an ideologue of the right.

In a 1978 article in The New York Times Magazine he said that "right-wing people like the pro-free-market argument, but don't like the arguments for individual liberty in cases like gay rights - although I view them as an interconnecting whole. ..."

Whether they agreed or disagreed with the political implication of the book, critics were nearly unanimous in their appreciation for Nozick's lively, accessible writing style. In a discipline known for arduous writing, Nozick's approach was hailed as a breath of fresh air.

He explained his approach in the article cited above: "It is as though what philosophers want is a way of saying something that will leave the person they're talking to no escape. Well, why should they be bludgeoning people like that? It's not a nice way to behave."

Despite the notoriety and influence that his first book brought him, Nozick moved on to explore very different territory in his second book, "Philosophical Explanations" (1981). This need to be intellectually on the move at all times characterized his career. He once told an interviewer, "I didn't want to spend my life writing 'The Son of Anarchy, State, and Utopia.'"

In "Philosophical Explanations," Nozick took on subjects that many academic philosophers had dismissed as irrelevant or meaningless, such as free will versus determinism and the nature of subjective experience, and why there is something rather than nothing. In dealing with these questions, he rejected the idea of strict philosophical proof, adopting instead a notion of philosophical pluralism.

"There are various philosophical views, mutually incompatible, which cannot be dismissed or simply rejected," he wrote in "Philosophical Explanations." "Philosophy's output is the basketful of these admissible views, all together." Nozick suggested that this basketful of views could be ordered according to criteria of coherence and adequacy and that even second- and third-ranked views might offer valuable truths and insights.

Nozick continued to develop his theory of philosophical pluralism in his next book, "The Examined Life" (1989), an exploration of the individual's relation to reality that, once again, emphasized explanation rather than proof.

In his book, "The Nature of Rationality" (1995), Nozick asked what function principles serve in our daily life and why we don't simply act on whim or out of self-interest. "Socratic Puzzles" (1997) was a collection of essays, articles, and reviews, plus several examples of Nozick's philosophical short fiction.

His next work, "Invariances: The Structure of the Objective World," (2001) looks at the nature of truth and objectivity and examines the function of subjective consciousness in an objective world. It also scrutinizes truth in ethics and discusses whether truth in general is relative to culture and social factors.

Nozick's teaching followed the same lively, unorthodox, heterogeneous pattern as his writing. With one exception, he never taught the same course twice. The exception was "The Best Things in Life," which he presented in 1982 and '83, attempting to derive from the class discussion a general theory of values. The course description called it an exploration of "the nature and value of those things deemed best, such as friendship, love, intellectual understanding, sexual pleasure, achievement, adventure, play, luxury, fame, power, enlightenment, and ice cream."

Speaking without notes, Nozick would pace restlessly back and forth, an ever-present can of Tab in his hand, drawing his students into a free-ranging discussion of the topic at hand.

He once defended his "thinking out loud" approach by comparing it with the more traditional method of giving students finished views of the great philosophical ideas.

"Presenting a completely polished and worked-out view doesn't give students a feel for what it's like to do original work in philosophy and to see it happen, to catch on to doing it."

He also used his teaching as a way of working out his ideas, often leading to views that he would later present in book form. "If somebody wants to know what I'm going to do next, what they ought to do is keep an eye on the Harvard course catalogue," he once told an interviewer.

Nozick, who grew up in Brooklyn and attended public school there, came to philosophy via a paperback version of Plato's "Republic," which he found intellectually thrilling. Nozick described the experience in his 1989 book, "The Examined Life" - "When I was 15 years old, or 16, I carried around on the streets of Brooklyn a paperback copy of Plato's ‘Republic'; front cover facing outward. I had read only some of it and understood less, but I was excited by it and knew it was something wonderful."

Nozick obtained an A.B. degree from Columbia College in 1959, and M.A. and Ph.D. degrees from Princeton in 1961 and 1963, respectively. After stints at Princeton and the Rockefeller University, Nozick came to Harvard as a full professor in 1969, at the age of 30. He became Arthur Kingsley Porter Professor of Philosophy in 1985 and in 1998 was named the Joseph Pellegrino University Professor.

Nozick was the recipient of many awards and honors, among them the Presidential Citation from the American Psychological Association in 1998, which described him as "one of the most brilliant and original living philosophers."

Nozick was also a fellow of the American Academy of Arts and Sciences, a member of the Council of Scholars of the Library of Congress, a corresponding fellow of the British Academy, and a senior fellow of the Society of Fellows at Harvard. He served as the president of the American Philosophical Association's Eastern Division from 1997 to 1998, was a Christensen visiting fellow at St. Catherine's College, Oxford University, 1997, and a cultural adviser to the U.S. Delegation to the UNESCO Conference on World Cultural Policy in 1982.

In the spring of 1997, he delivered the six John Locke Lectures at Oxford University. He held fellowships from the Guggenheim Foundation, the Rockefeller Foundation, the National Endowment for the Humanities, and the Center for Advanced Study in the Behavioral Sciences.

He is survived by his wife, Gjertrud Schnackenberg, and his two children, Emily Sarah Nozick and David Joshua Nozick.

Nozick will be buried in a private ceremony. A memorial service is being planned for sometime in February.

David Lewis, Philosopher And Metaphysician, Dies at 60 (By Sarah Boxer, NYT)

"David Lewis, Philosopher And Metaphysician, Dies at 60 (By Sarah Boxer, NYT). David Kellogg Lewis, a metaphysician and a philosopher of mind, language and logic at Princeton University, died on Sunday at his home in Princeton, N.J. He was 60. The cause was heart failure, Princeton University said. Mr. Lewis was once dubbed "a mad-dog modal realist" for his idea that any logically possible world you can think of actually exists. He believed, for instance, that there was a world with talking donkeys. Mark Johnston, the chairman of Princeton's philosophy department, called Mr. Lewis "the greatest systematic metaphysician since Gottfried Leibniz." And Alex Oliver, reviewing one of Mr. Lewis's recent books, "Papers in Metaphysics and Epistemology," in The Times Literary Supplement of London, said he was "the leading metaphysician at the start of this century, head and beard above his contemporaries." Others considered Mr. Lewis's philosophy pure nonsense, a twisting of ordinary language. Mr. Lewis wrote "Convention: A Philosophical Study" (1969), which won the Matchette Prize in Philosophy for scholars under 40; "Counterfactuals" (1973); "On the Plurality of Worlds" (1986); "Parts of Classes" (1991); and many papers. In "Counterfactuals," he introduced his curious turn on the idea of possible worlds, explored by Saul Kripke and before that by the pre-Socratic philosopher Parmenides: "I believe, and so do you, that things could have been different in countless ways. But what does this mean? Ordinary language permits the paraphrase: there are many ways things could have been besides the way they actually are. I believe that things could have been different in countless ways; I believe permissible paraphrases of what I believe; taking the paraphrase at its face value, I therefore believe in the existence of entities that might be called `ways things could have been.' I prefer to call them `possible worlds.'" In "On the Plurality of Worlds," Mr. Lewis argued that the actual world is just one among an infinite number of worlds, each one equally real. This view comported well with the "many worlds" interpretation of quantum mechanics. But some philosophers argued that Mr. Lewis was simply misusing the word "real." Mr. Lewis was also considered by some philosophers a Meinongian, a follower of Alexius Meinong, who believed that there were things that had being but not existence. Mr. Lewis's views of possible worlds often led to talk about the reality of Conan the Barbarian, Middle Earth and the planets depicted in "Star Trek" episodes. They also evoked some skepticism. In an article this year titled "Multiverses and Blackberries" in The Skeptical Inquirer, Martin Gardner wrote, "Lewis seriously maintains that every logically possible universe — that is, one with no logical contradictions such as square circles — is somewhere out there." This view, he added, goes back to Leibniz's idea "that God considered all logically possible worlds, then created the one he deemed best for his purposes." The "mad multiverse" espoused by Mr. Lewis, Mr. Gardner wrote, is the stuff of fiction, including Larry Nivens's 1969 story "All the Myriad Ways"; Frederick Pohl's 1986 novel, "The Coming of the Quantum Cats"; and Jorge Luis Borges's story "The Garden of Forking Paths." But, Mr. Gardner said, it had no business in the philosophy of science. Born in Oberlin, Ohio, on Sept. 28, 1941, Mr. Lewis was educated at Swarthmore College, Oxford University and Harvard, where he earned his doctorate, under the supervision of W. V. Quine, in 1967. He taught philosophy at U.C.L.A. from 1966 to 1970, and then at Princeton University, where he became the Class of 1943 University Professor of Philosophy. He was a fellow of the American Academy of Arts and Sciences and received honorary degrees from the University of York and Cambridge University, in England. Mr. Lewis, who loved Australia, also got an honorary degree from the University of Melbourne and was an honorary fellow of the Australian Academy of the Humanities. He is survived by his wife, Stephanie; a brother, Donald; and a sister, Ellen. Paul Benacerraf, the James McDonnell Distinguished University Professor of Philosophy at Princeton, said Mr. Lewis loved riding trains. "He was a railroad buff; he had elaborate model trains," he said. Mr. Lewis would often hop on a train in the morning and spend the entire day on the rails, traveling to other worlds and back again."

"To the Editor [of the NYT]: We strongly disagree with your Oct. 20 obituary's characterization of the philosopher David Kellogg Lewis of Princeton University. You mention his views about "possible worlds," but you would never know from your obituary that most of his work was independent of these views. You don't have to believe in possible worlds to accept his seminal treatment of linguistic convention, his version of materialism in the philosophy of mind, his contribution to the role of probability in the natural sciences, his ingenious theory of personal identity over time or his account of the compatibility of free will and determinism. In these domains, as in many others, Mr. Lewis's work has not just been influential. It has set the agenda for recent work in philosophy. MARK JOHNSTON -- GIDEON ROSEN -- Princeton, N.J., Oct. 23, 2001. The writers are, respectively, chairman and associate professor in the philosophy department, Princeton University."

"Princeton philosopher who formulated ground-breaking theories on everything from language to identity to alternative worlds. Jane O'Grady. Guardian. Parallel universes and other possible worlds are currently much in vogue, as evinced by the films Sliding Doors and Possible Worlds. In science, these intriguing intuitions assume rigour through the many-worlds theory of quantum mechanics, and in philosophy through the possible-worlds theories of the Princeton professor David Lewis, who has died, aged 60, of complications from diabetes. Lewis is most celebrated for his "modal realism", a theory which argues that possible worlds are not just a concept for explaining possibility and necessity, but as real as our own universe. He also produced outstandingly innovative theories on scientific laws, chance, probability, causation, the identity and functionalist theories of mind, (linguistic) convention and a vast range of other issues. Together, his ideas in different areas form a grand, all-embracing theory, and to his many devotees he ranks as one of the great metaphysicians in this, or perhaps any, era. Born in Oberlin, Ohio, Lewis was an undergraduate at Swarthmore College, Pennsylvania, initially in chemistry."

"While spending a term at Oxford, he attended lectures by Gilbert Ryle, who had disputed the existence of the mind in his controversial book, The Concept Of Mind, and became so enthused that he changed to philosophy on returning to the US."

"After graduating in 1964, Lewis took a PhD at Harvard under the great Willard van Orman Quine (obituary, December 30 2000). Even as a graduate, Lewis had enormous standing in the philosophical world. The much-debated theory that had replaced Ryle's analytic behaviourism argued that mental states will ultimately turn out to be nothing but physical processes in the brain, and JJC Smart, one of the initiators of this identity theory of mind, visited Harvard in the mid-1960s. "I taught David Lewis," he said afterwards, "or rather, David Lewis taught me," and in 1966, the year before obtaining his doctorate, Lewis produced the essay An Argument For The Identity Theory, which improved on Smart's position. Typically, Lewis not only got to the nerve of the issue, but took it in a new direction. Trying to rebut the commonsensical dualist objection that surely "experiences are non-physical and physically inefficacious", he said that experiences should be (in fact, implicitly were) considered as the effects of certain stimuli and the causes of certain behaviour. Pain, for instance, is whatever causally links a certain sensory input (having your eyes gouged out, for instance) with behavioural output (screaming) and other mental states (urgent desire to be rid of the pain). Neural science will eventually show this causal "whatever" to be a particular state in the brain, just as (Lewis wrote in his 1972 paper, Psychophysical And Theoretical Identifications) a detective who knows in detail the roles - but not the identities - of conspirators involved in a murder will ultimately be able to establish who exactly these conspirators are. Simultaneously, Lewis was setting the agenda in other areas of philosophy. In 1966, Convention: A Philosophical Study (his rehashed thesis) broke new ground in the philosophy of language, in which it remains a seminal work. He became assistant professor at the University of California, Los Angeles, in the same year, associate professor at Princeton in 1970, and full professor there three years later. In Counterfactuals (1973), and many articles before and after it, he was working out his controversial theory of modal realism, which is most fully expressed in On The Plurality Of Worlds (1986). Since Leibniz's formulation of the idea in the 17th century, philosophers had treated possible worlds as a purely conceptual notion useful for explaining concepts of possibility and necessity: anything that we can coherently conceive as possible can be called a possible world, but if something is necessarily true, then it is true in all possible worlds. Lewis argued that possible worlds were not concepts, but real - existing in the same way as our universe does and no different from it except in the details of what happens there. "The inhabitants of other worlds may truly call their own worlds actual, if they mean by 'actual' what we do," just as "the inhabitants of other times may call their times 'present', if they mean by 'present' what we do". After all, "our present time is only one time among many". "Actual" is on a par with "I", "here" or "now"; what it refers to depends on who says it and the world at which (Lewis's terminology) it is said. As for counterfactuals, which appeal to what might have been, the counterfactual "If he hadn't pressed the alarm, she would have been killed," for instance, is true if there is a possible world in which he didn't press the alarm, and she was killed, that is more similar to our own world than one in which he pulled the cord and she wasn't killed. Of course, the person who was killed is only a counterpart to her equivalent in the actual world, even if both play similar roles in each of their worlds. And there is no spatial, temporal or causal connection between possible worlds and our own. To postulate the reality of possible worlds is to spin metaphysics out of logic, and when Lewis spoke about it he usually met with "an incredulous stare" - this expression became a philosophical joke and the name of a section of On The Plurality Of Worlds. Yet it was, he said, the only way to make sense of everything. Soon incredulity gave way to a cottage industry of objections and interpretations. For what possible worlds actually are (and virtually no one, perhaps not even Lewis, accepted their reality) does not affect the brilliant, sophisticated way he used them, analysing problematic notions in causation, universals, the content of thought, properties, probability, and the nature of propositions. Modal realism mowed down problems like a combine harvester (to paraphrase an admiring colleague) not only in philosophy, but in semantics, linguistics, game theory and economics. Sometimes Lewis spoke as if he discovered his intentions, both practical and intellectual, almost by trial and error, and the same sort of induction seems to have occurred with his metaphysics. He said in the introduction to his Philosophical Papers Volume II (1986) that, like any analytic philosopher, he had set out to tackle problems piecemeal, but that he seemed almost inadvertently to have produced a coherent, unified thesis. This, which he called "Humean supervenience", says that the world is a "vast mosaic" of tiny facts and, at any instant, what it is, and what we can truly say about it, depends upon the patterns that these exemplify, just as in a pointillist picture what is depicted is determined by the dots. Nothing that happens at one point logically fixes what happens at any other point, but it is the totality of what happens that fixes everything else. All Lewis's theories seemed to converge in this thesis, he said, but he admitted that there was a bug in the system - chance - which could subvert the whole thing. This was a problem he was still struggling with at the last. Lewis expressed his esoteric ideas in brisk, sturdy, lucid prose, whether on paper or orally, but he was famously incapable of small talk. Shy, pale and lengthily bearded, he was affectionately nicknamed Machine in the Ghost (turning Ryle's disparagement of dualism on its head). But he could be unflamboyantly funny, especially in print, and his philosophical examples are witty without facetiousness or self-congratulation (a famous article contrasted a Martian whose response to painful stimuli is the inflation of cavities in his feet with a madman whose reaction is indifference). Lewis was astoundingly modest and unpompous for a successful philosopher, always ready to respond to criticism, and unfailingly generous to students. Perhaps his dislike of pretentiousness and convention led to his love of Australia. His contacts with the Australian theorists Jack Smart and David Armstrong led to a lasting connection with the country, where he became a huge philosophical figure. Almost every year he and his wife stayed there for two or three months, and he became an aficionado of Australian rules football (he was buried with the Essendon club's season ticket), and its Bush ballads, birds and trains. English railways were his favourites, however; he would travel on them for the sake of the journey. His basement was occupied by a model railway set, which the privileged were also allowed to play with, and walls were knocked down to accommodate it. Asked why he did not have a credit card, he said he did not want to be in debt. Lewis restored philosophical respectability to systematic metaphysics. Like Hume, he tried to reconcile a scientific conception of the world with how it actually appears to us. He called himself "a commonsensical fellow (except where unactualised possible worlds are concerned)". The paper he was last working on used possible worlds to link personal identity with immortality. This may not sound commonsensical, but it is poignant for the many people that loved him as a philosopher and as a man. He is survived by his wife, Steffi. David Kellogg Lewis, philosopher, born September 28 1941; died October 14 2001."

Posted 4/2/01

When Ludwig met Karl...

Did Wittgenstein threaten Popper with a red-hot poker in Cambridge 55 years ago? John Eidinow and David Edmonds on the truth behind a row described as a watershed in 20th-century philosophy

Saturday March 31, 2001
The Guardian

On the evening of Friday October 25 1946, the Cambridge Moral Science Club - a discussion group for the university's philosophers and philosophy students - held a meeting. The members assembled in King's College at 8.30pm, in a set of rooms in the Gibbs Building - number three on staircase H.

Although its tenant was a don, Richard Braithwaite, H3 was just as neglected as the other rooms in the building, squalid, dusty and dirty. Heating was dependent on open fires and the inhabitants protected their clothes with their gowns when humping sacks of coal.

That evening, the guest speaker was Dr Karl Popper, up from London to deliver an innocuous-sounding paper, Are There Philosophical Problems?. Among his audience was the chairman of the club, Professor Ludwig Wittgenstein, considered by many to be the most brilliant philosopher of his time. Also present was Bertrand Russell, who for decades had been a household name as a philosopher and radical campaigner.

Popper had recently been appointed to the position of reader in logic and scientific method at the London School of Economics. The Open Society and Its Enemies, his remorseless demolition of totalitarianism, had just been published in England. It had immediately won him a select group of admirers, among them Russell.

This was the only time these three great philosophers - Russell, Wittgenstein and Popper - were together. Yet, to this day, no one can agree precisely what took place. What is clear is that there were vehement exchanges between Popper and Wittgenstein over the fundamental nature of philosophy. These instantly became the stuff of legend. An early version of events had Popper and Wittgenstein battling for supremacy with red-hot pokers.

In Popper's account, found in his intellectual autobiography, Unended Quest, published in 1974, more than two decades after Wittgenstein's death, he put forward a series of what he insisted were real philosophical problems. Wittgenstein summarily dismissed them all. Popper recalled that Wittgenstein "had been nervously playing with the poker", which he used "like a conductor's baton to emphasise his assertions", and when a question came up about the status of ethics, Wittgenstein challenged him to give an example of a moral rule. "I replied: 'Not to threaten visiting lecturers with pokers.' Whereupon Wittgenstein, in a rage, threw the poker down and stormed out."

Those 10 or so minutes in October 1946 still provoke bitter disagreement. Above all, one dispute remains heatedly alive: did Karl Popper lie in his published account of the meeting?

If he did, it was no casual embellishing of the facts but directly concerned two ambitions central to his life: the defeat at a theoretical level of fashionable 20th-century linguistic philosophy and triumph at a personal level over Wittgenstein, the sorcerer who had dogged his career.

To an outsider, a violent confrontation between Wittgenstein and Popper might have seemed implausible. They were both Jews from Vienna and, superficially, they had in common a civilisation - and its dissolution. Although Wittgenstein was the older by 13 years, they had shared the cultural excitement of the last years of the Austro-Hungarian Empire. They had in common, too, the impact on their lives of the lost first world war, the attempt to raise a modern republic on the ruins of the monarchy, the descent into the corporate state, and the maelstrom of Hitler and Nazism. With their Jewish origins, interest in music, contacts with cultural radicals, training as teachers, and their connections with the fountainhead of logical positivism, the Vienna Circle, Wittgenstein and Popper had many potential links. That they had never met was remarkable.

Of the great figures in 20th-century philosophy, only a very few have given their names to those who follow in their path. That one can be identified as a Popperian or a Wittgensteinian is a testament to the originality of these philosophers' ideas and the power of their personalities. Those extraordinary qualities were on display in H3. The thrust of the poker becomes a symbol of the two men's unremitting zeal in their search for the right answers to the big questions.

Three years after Popper's death, a memoir published in the proceedings of one of Britain's most learned bodies, the British Academy, recounted essentially Popper's version of events. It brought down a storm of protest on the head of the author, Popper's successor at the LSE, Professor John Watkins, and sparked off an acerbic exchange of letters in the Times Literary Supplement. A fervent Wittgenstein supporter who had taken part in the meeting, Professor Peter Geach, denounced Popper's account of the meeting as "false from beginning to end". A robust correspondence followed as other witnesses or later supporters of the protagonists piled into the fray.

There was a delightful irony in the conflicting testimonies. They had arisen between people all professionally concerned with theories of epistemology (the grounds of knowledge), understanding and truth. Yet they concerned a sequence of events where those who disagreed were eyewitnesses on crucial questions of fact.

But why was there such anger over what took place more than half a century before, in a small room, at a regular meeting of an obscure university club, during an argument over an arcane topic?

Of the 30 present that night, nine, now in their 70s or 80s, responded by letter, phone and, above all, email from across the globe to appeals for memories of that evening. Their ranks include a former English high court judge, Sir John Vinelott. There are five professors. Professor Peter Munz had come to St John's from New Zealand and returned home to become a notable academic. His book, Our Knowledge of the Search for Knowledge, opened with the poker incident: it was, he wrote, a "symbolic and in hindsight prophetic" watershed in 20th-century philosophy.

Professor Stephen Toulmin is an eminent philosopher, co-author of a demanding revisionist text on Wittgenstein, placing his philosophy in the context of Viennese culture and fin de siècle intellectual ferment. As a young King's research fellow, he turned down a post as assistant to Karl Popper.

Geach, an authority on logic, lectured at Birmingham University, and then at Leeds. Professor Michael Wolff specialised in Victorian England, and his academic career took him to the US. Peter Gray-Lucas became an academic and then switched to business, first in steel, then photographic film, then papermaking. Stephen Plaister became a classics master.

"Consider this poker," Geach hears Wittgenstein demand of Popper, picking up the poker and using it in a philosophical example. But, as the discussion rages on between them, Wittgenstein is not reducing the guest to silence (the impact he is accustomed to), nor the guest silencing him (ditto). Finally, and only after having challenged assertion after assertion made by Popper, Wittgenstein gives up. At some stage he must have risen to his feet, because Geach sees him walk back to his chair and sit down. He is still holding the poker. With a look of great exhaustion, he leans back in his chair and stretches out his arm towards the fireplace. The poker drops on to the tiles of the hearth with a little rattle. At this point Geach's attention is caught by the host, Braithwaite. Alarmed by Wittgenstein's gesticulating with the poker, he is making his way in a crouching position through the audience. He picks up the poker and somehow makes away with it. Shortly afterwards, Wittgenstein rises to his feet and, in a huff, quietly leaves the meeting, shutting the door behind him.

Wolff sees that Wittgenstein has the poker idly in his hand and, as he stares at the fire, is fidgeting with it. Someone says something that visibly annoys Wittgenstein. By this time Russell has become involved. Wittgenstein and Russell are both standing. Wittgenstein says: "You misunderstand me, Russell. You always misunderstand me."

Russell says: "You're mixing things up, Wittgenstein. You always mix things up."

Munz watches Wittgenstein suddenly take the poker - red hot - out of the fire and gesticulate with it angrily in front of Popper's face. Then Russell takes the pipe out of his mouth and says firmly: "Wittgenstein, put down that poker at once!"

Wittgenstein complies, then, after a short wait, gets up and walks out, slamming the door.

From Gray-Lucas's standpoint, Wittgenstein seems to be growing very excited about what he obviously believes is Popper's improper behaviour and is waving the poker about. Wittgenstein is acting in "his usual grotesquely arrogant, self-opinionated, rude and boorish manner. It made a good story afterwards to say that he had 'threatened' Popper with a poker."

Plaister, too, sees the poker raised. It really seems to him the only way to deal with Popper, and he has no feeling of surprise or shock. To Toulmin, sitting only six feet from Wittgenstein, nothing at all out of the ordinary is occurring. He is focusing on Popper's attack on the idea that philosophy is meaningless and his production of various examples. A question about causality arises and at that point Wittgenstein picks up the poker to use as a tool in order to make a point about causation. Later in the meeting - after Wittgenstein has left - he hears Popper state his poker principle: that one should not threaten visiting lecturers with pokers.

Vinelott alone sees the crucial point - whether Popper makes what was probably an attempt at a joke to Wittgenstein's face - in Popper's way. Vinelott hears Popper utter his poker principle and observes that Wittgenstein is clearly annoyed at what he thinks is an unduly frivolous remark. Wittgenstein leaves the room abruptly, but there is no question of the door being slammed.

The debate continues and the story has achieved the status, if not of an urban myth, then at least of an ivory-tower fable. The story goes beyond the characters and beliefs of the antagonists. It is also the story of the schism in 20th-century philosophy over the significance of language: a division between those who diagnosed traditional philosophical problems as purely linguistic entanglements and those who believed that these problems transcended language. In the end, of course, it is the story of a linguistic puzzle in itself: to whom did Popper utter what words in that room full of witnesses, and why?

And what of the sine qua non of this story? The fate of the poker remains a mystery. Many have searched for it in vain. According to one report, Braithwaite disposed of it - to put an end to the prying of academics and journalists.

• This is an edited extract from Wittgenstein's Poker: the Story of a Ten- Minute Argument Between Two Great Philosophers, published on April 9 by Faber, price £9.99. To order a copy for £7.99 plus p&p, freephone Guardian CultureShop on 0800 3166 102.

Posted 8/31/00


Just a quick note to let people know that we've introduced a couple more interactive philosophy games:
Staying Alive - a lighthearted game of personal identity:
So you think you're logical?
Also, if you haven't yet completed the TPM 2000 Survey, this is your last chance. It is here:
Dr Jeremy Stangroom
The Philosophers' Magazine