Wednesday, April 13, 2005

Philosophical Barn Stuff

Physicists inherit an aversion to philosophy, but a bestselling book by a Princeton philosopher has me thinking that philosophy might be pretty cool after all.

The physicist's aversion is a legacy of luminaries. "It has often been said, and certainly not without justification, that the man of science is a poor philosopher." So quoth Einstein. And Richard Feynman, legendary hero to many physicists, thought that philosophy, as an exercise in pure thought, is fatally flawed: lacking the empirical constraints featured in experimental and observational sciences, it is hopelessly consigned to endless rounds of verbiage and hair-splitting that go in circles and advance nowhere. In other words, it's all BS (Barn Stuff---not unlike blog discussions!). Ironically, Feynman's son chose to study philosophy.

But I think even Feynman would be pleased with this philosophical work. Unlike philosophers (or lawyers or mathematicians, for that matter), physicists are supposed to be comfortable---when occasion warrants---hacking through a problem by using physical intuition (a.k.a. flying by the seat of one's pants), with a casual disregard for airtight logic that brings tears to the eyes of mathematicians. (For example, I think calculus was fruitfully exploited for a couple hundred years after it was invented by Newton and Leibniz before mathematicians put it on a rigorous logical footing.) The lack of rigor and horrifyingly cavalier dismissal of potential loopholes is justified by the fact that, being an experimental enterprise, the data can be relied upon in the end to highlight any mistakes. Hence one of the outcomes of a physicist's training should be a sense of intuition, a nose for the general direction towards which the data are pointing, especially at the margins where the data are still incomplete. As part of this, a physicist tends to develop a finely honed BS detector. Feynman exemplified this in all aspects of life, not just his science; he was uncompromisingly opposed to phoniness in all its manifestations.

The book is short; it's actually only an essay, reworked into a book with liberal use of big margins and large typefaces. But if you don't want to actually buy and read the work itself (I haven't either, I'm BSing my way through this post!), you can read a newspaper article, or watch a segment on Comedy Central's Daily Show with Jon Stewart---which should be enough to allow you, too, to BS your way through a conversation about it around the water cooler, or over the dinner table.


Before science was natural science, it was "natural philosophy." And despite the popular degradation of the term, philosophy still pursues "metaphysics" as serious inquiry. I wonder how much of the scientific loathing of philosophy comes from a desire to distance science from the clear genealogical links between the two? 
Comment by Dave | 4/13/2005 12:56:00 PM  

I wrote a post  a few days back arguing that the supposed divide between philosophy and science is a myth. 
Comment by clark | 4/13/2005 02:39:00 PM  

Dave,  I think there's something to that. I recently heard a talk by a historian of science, who discussed the Sokal affair, and related it to the struggle in the 19th century for "natural science" to carve out a niche against the classics, and how the "natural scientists" made their case by pointing to empirical testability as their unique criterion. I suppose modern scientists inherit the argument without knowing the circumstances of its original articulation. 
Comment by Christian Y. Cardall | 4/13/2005 03:37:00 PM  

The problem is that scientists have to be naive to think that they are the only ones who use empirical testability as a criteria. Indeed positivism was in certain ways a move to think philosophy purely in terms of that criteria. Likewise the problem with empirical testability as a ground is that most modern theoretical physics lacks any such testability. Does that mean that the superstring theorists and loop quantum gravity theorists ought be cast out of physics departments and put in the humanities? One can also make the claim that to do science intrinsically requires one to engage in philosophical thinking  even if one pretends one isn't doing it. 
Comment by Clark | 4/13/2005 04:03:00 PM  

Clark,  thanks for the pointer to your interesting post. The thing I didn't see you elaborate much on was the distinguishing feature of testability. You make a good point about superstring theory, but in fact that's a bone of contention within the physics community. Many are beginning to question its place in physics, by insulting it as 'metaphysics' or (much worse) 'theology.' There will be a popular book by Lawrence Krauss later this year along these lines.

I should also acknowledge that I was underhanded in my quote of Einstein. My deliberate plan was (and maybe still is, I guess) to use this confession as a starting point for a separate post. The quote was the opening sentence of an article in which he went on to argue that theoretical physics had reached a point (by the 20th century) where it became necessary to do some "philosophy."

But his argument was only with respect to methodology of arriving at physical theory, not judgment of the end product. Specifically, that phenomena under consideration have become so far removed from common experience that induction is inadequate, and one has to look to principles like unification, mathematical consistency, etc. as a starting point in the search for new laws. But he was committed to testability of the final product, and his unbelievable (pre-1930s) output has been stunningly validated empirically.
Comment by Christian Y. Cardall | 4/13/2005 04:10:00 PM  

Clark, I was writing my last comment before seeing your last one, but I think we probably agree more than disagree. Einstein engaged in "philosophizing" to great effect---in particular, mathematical consistency and what might be called epistemology (relating to thinking clearly about how measurements are actually done) were integral to the development of relativity.

But in the end it also got him off into la-la land---a cautionary tale that "philosophizing" can be dangerous. I guess I'd say it can play an important role, even necessary (especially now) as one tries to develop theories. But I think I would also say that in the end it has to produce (or at the very least aim for and seek to find) testable predictions to be considered science.
Comment by Christian Y. Cardall | 4/13/2005 04:19:00 PM  

When you say Einstein went to "la-la-land" what do you mean? Have you read Fine's The Shaky Game . While I don't buy Fine's own interpretation of QM, I think he offers compelling arguments that the typical view of the later Einstein is completely wrong. 
Comment by Clark | 4/13/2005 05:33:00 PM  

BTW - with the complaint by some against Superstring theory, I think that they're on shaky ground. The fact is that this sort of thing has always been part of science. Some scientists like to think that philosophy has no part in science, not even noticing that such a claim is self-refuting. (It is a philosophical claim) It ends up being little more than a repeat of the old distrust between theoreticians and experimentalists, albeit with the lines drawn a little differently. (Feynman is, after all, the classic theorist, but he was a big critic of superstrings) | 4/13/2005 05:35:00 PM  

Clark, actually I was thinking of his unfruitful unified field work. It was a good instinct, but premature. It turned out to be the case that it was necessary to observe a bevy of new particles before it could be discerned how progress toward unification might be made. Importantly, it was a demonstration that induction from new observations was  necessary at that stage, that "philosophy" was insufficient, however well it may have served his early brilliant successes. It may be that similarly, such new, different, surprising data might be necessary to develop something like superstring theory into a successful Theory of Everything. Sadly, such data may be technologically out of reach, worlds without end---which may mean that "dreams of a final theory" may never be fulfilled.

Regarding QM, I haven't read the book you mentioned. I suppose I'd allow that QM is an area where philosophizing might help. In fact the Einstein's article I cited above was one that was essentially arguing philosophically for realism. We can only wonder what he would have thought had he lived to see Bell's theorem, its recent experimental confirmation, and the increasing number of experiments demonstrating quantum effects in mesoscopic (and even macroscopic) systems, e.g. Bose-Einstein condensates and the various systems being developed in connection with quantum computation. I suspect it is such new observations as these that experimentally probe the quantum/classical boundary, more than "philosophizing", that will catalyze an improved understanding of quantum mechanics.

But again, I won't deny that the development of physical laws involves philosophizing. Equations only become physical law to the extent their variables can be conceptually linked to operational procedures, and constructing these notions is certainly "philosophy" in some sense.
Comment by Christian Y. Cardall | 4/13/2005 08:08:00 PM  

Bertrand Russell noted that once a philosophical question is answered, it ceases to be a philosophical question. Geometry, astronomy, botany, biology, algebra, physics, chemestry, and logic all started as philosophy. Physics is, in my opinion, among the most philosophical sciences--compare it to, say, botany or biology. Perhaps this proximity of physics to philosophy makes physicists especially sensitive about the differences between the two. 
Comment by Arturo Toscanini | 4/15/2005 05:55:00 PM  

Arturo, I'm not quite sure I understand the sense in which you think physics is "philosophical." In the sense of the Russell quote, that it is not yet answered? In the sense that it asks "philosophical" questions aiming at a unifying, explanatory logical framework, as opposed to simply being descriptive or categorizing (like botany or stamp collecting)?
Comment by Christian Y. Cardall | 4/15/2005 08:45:00 PM  

As Plato said, "those whose hearts are fixed on Reality itself deserve the title of Philosophers." The question of the ultimate constituents of matter is among the earliest asked by philosophers. Physics and chemistry are very much part of the empirical outgrowth of the pursuit of answers to this question. 
Comment by Arturo Toscanini | 4/15/2005 09:52:00 PM  



<< Home