It’s hard to imagine a time when big-time philosophers roamed the earth as true public figures, in search of weighty issues, faculty positions, and total intellectual superiority over fellow philosophers who dared to argue with them.

Such was the time in the first half of the 20th Century, with one of the main battlegrounds the post-war scene at Cambridge University, home base of Bertrand Russel, GE Moore, and of course Ludwig Wittgenstein - the iconoclastic bad boy of philosophy, cult figure, and master of cryptic utterances who had a devastating penchant for eviscerating the work of philosophers he disagreed with - which was most other philosophers without the initials LW.

The scene was the Moral Science Society, which was was holding their monthly meeting on October 25, 1946. Karl Popper - at that time just starting a position at the London School of Economics, was already causing a stir with his The Logic of Scientific Discovery - was in town presenting a talk titled Are There Philosophical Problems?

The head of the MSD was none other than Ludwig W. Wittgenstein, scion of one of the wealthiest families in pre-war Austria, who had renounced all his wealth to live an ascetic life of the mind, spirit, and body that is so improbably eccentric that he and his ideas are recurring figures and themes in many fictional stories that need a touch of the bizarre (e.g. The World As I Found It, by Bruce Duffy, A Philosophical Investigation by Philip Kerr, Wittgensteins’ Mistress by David Markson).

Apparently Popper was no no shrinking violet either : a truly fesity, take-no-philosophical-prisoner scold according to many contemporaries.

Back to the dom’s room at Cambridge. You get the picture: smoky, with drab walls, scuffed, darkened oak chairs and table, leaded glass separators on the casement windows, bottles of port, an old fireplace with soot-covered bricks inside, and… a fireplace poker soon to be infamous for the briefest of philosophical battles. What happened in that room is the stuff of philosophical lore - 10-minute argument that flashed between Wittgenstein and Popper that is still recounted and debated today.

(Note: This post is motivated by a marvelous book by David Edmonds and John Eidinow on this incident titled Wittegenstein’s Poker: The Story of a Ten-Minute Argument Between Two Great Philosophers. E&E do a masterful job of explaining the foibles and eccentricities of K and L as shaped by their personal history in the tumultuous first-half of the 20th Century. Read it!)

The main part of the story, as recounted by Edmonds & Eidinow:

Popper 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 emphasize 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 of the room, banging the door behind him."

I’m not giving anything away by pointing out that this tale is recounted by Popper, and there are real questions about whether the event transpired as he describes., or has been embellished at the sake of Ludwig, who apparently was known to often leave rooms by storming out in a blaze of philosophical muttering. Read Wittgenstein’s Poker for the definitive forensics of the event.

This story is fascinating to me for reasons beyond the intense personalities that could lead to such an eruption. Both Wittgenstein and Popper were obsessed with the nature of the world and what could be known about it, but both could not be further apart on method. Thus the main seeds of the argument grew from Wittgenstein’s approach to philosophical issues as problems in language, while Popper was a "big issue" guy, with works on everything from the distinction between science and non-science to the dangers of totalitarianism.

Of specific relevance to the Chaos and Fractals course is Popper’s description of falsifiablitiy as a necessary condition for a scientific theory. (We do spend some time reading about the 20th-Century schools of mathematical philosophy, including logical positivism and the verificationist stance of the Vienna Circle - the antithesis of Popper’s falsifiability.) Basically, a falsifiable theory is one for which there is no logical reason why an experimental observation can’t show the theory to be incorrect. Popper necessarily then must have prediction as a major hallmark of any theory - without this, there’s no way to gauge the correctness of the theory. What to make then of Chaos Theory? One of the features of Chaos is that predictions can be notoriously unreliable due to sensitive dependence on initial conditions. Thus the theory itself contains as a prediction its own unpredictability. Does this make Chaos non-scientific because there is then nothing in principle that is observable that would refute this unpredictability?

This dilemma/paradox is typical of any statement that is defined recursively and in which it describes itself - "This sentence is not true" being a standard example. In the case for falsifiability, physical law - one which we believe describes a certain feature of the universe, and which we believe to be an essential feature of the world (e.g. Newton’s Law of Gravitation) occupies a real place of tension between absolute true reality, and a precarious about-to-be-refuted relationship. This convoluted reasoning reminds me of Groucho Marx’s "I refuse to belong to any club that will accept me as a member," and it clearly got to Wittgenstein, whose own views on science are notoriously difficult to parse. Here’s a nice collection of statements from Tractatus Logico-Philosophicus complied by Robert Brow in his interesting essay Wittgenstein, Science, and God:

"The world is everything that is the case. The world is the totality of facts, not of things. The facts in logical space are the world" (1.1-13). In any scientific system "the totality of true propositions is the total natural science (or the totality of the natural sciences)" (4.111). It is the propositions which are possible in our scientific language, which "show the logical form of reality. They exhibit it" (4.121). Which means that "empirical reality is limited by the totality of objects. The boundary appears again in the totality of elementary propositions" (5.5561) "The limits of my language mean the limits of my world" (5.61).

On the other hand, Wittgenstein himself was a master of vertiginous meta-sentences, one of which I have adopted as the underlying theme of the Chaos and Fractals course:

The fact that we can describe the motions of the world using Newtonian mechanics tells us nothing about the world. The fact that we do, does tell us something about the world.

Now back to the story of the poker and its truthiness. Popper no doubt knew that his talk would produce a very agitated Wittgenstein. Given Wittgenstein’s M.O., there’s no way Ludwig would not have done what he did. Therefore the outcome of the exchange between the two Austrians was not falsifiable and thus not scientific. It was, however, a thoroughly fascinating case of two philosoraptors locked in a brief, violent embrace of ideas. As they rumbled off to separate corners of the room, campus, and globe, the reverberations of this death match continue to illuminate the always passionate debates about the foundations of science and mathematics that continue to this day.

A version of it has even made Hollywood: Ryan O’Neal, of Love Story fame, was recently arrested after getting into a bizarre family/drug scene rage with his son Griffin. Both father and son claimed that the other tried to kill him with a - you guessed it - fireplace poker.