Change, progress, and philosophy in science
February 21, 2014 12 Comments
“Philosophy of science is about as useful to scientists as ornithology is to birds” is a quote usually attributed to Feynman that embodies a sentiment that seems all too common among scientists. If I wish to be as free as a bird to go about my daily rituals of crafting science in the cage that I build for myself during my scientific apprenticeship then I agee that philosophy is of little use to me. Much like a politician can hold office without a knowledge of history, a scientist can practice his craft without philosophy. However, like an ignorance of history, an ignorance of philosophy tends to make one myopic. For theorists, especially, such a restricted view of intellectual tradition can be very stifling and make scientific work seem like a trade instead of an art. So, to keep my work a joy instead of chore, I tend to structure myself by reading philosophy and trying to understand where my scientific work fits in the history of thought. For this, Bertrand Russell is my author of choice.
I don’t read Russell because I agree with his philosophy, although much of what he says is agreeable. In fact, it is difficult to say what agreement with his philosophy would mean, since his thoughts on many topics changed through his long 98 year life. I read his work because it has a spirit of honest inquiry and not a search for proof of some preconceived conclusion (although, like all humans, he is not always exempt from the dogmatism flaw). I read his work because it is written with a beautiful and precise wit. Most importantly, I read his work because — unlike many philosophers — he wrote clearly enough that it is meaningful to disagree with him.
I think the opaqueness of academic philosophy is one of the reasons why even philosophically minded scientists often disregard the contribution of current professional philosophers despite evidence to the contrary. To some extent, this is an excusable mistake given the need of mathematicians and scientists to focus on the developments in their own fields. For example, during my undergraduate years, I only took three courses from the philosophy department: introduction to deductive logic, philosophy of mind, and philosophy of mathematics. The first was a nice relaxation during the summer term between calculus 3 and probability, and was meant as a technical course but I can’t say that I learned much from it compared to logic and discrete math courses I took in math and computer science. The second was an exercise in what Russell would call muddleheaded thinking. The third, however, was enlightening. For the philosophy of mathematics, there was a clear subject matter, and the philosophers were keen to be precise in their language and ideas. The historic development was well presented and discussion invigorating. The mathematics involved was simple, of course, but still introduced me to new ideas. For example, that course was the first time I really started to reflect on computer-assisted proofs, a discussion that is recurring recently with the computer assisted progress on the Goldbach conjecture and the Erdős discrepancy problem.
In seeking asylum in mathematics, I was mirroring Russell’s early development. For the early Russell, logic and mathematics provided a barque of reason in the ocean of insanity that is human life. To be sure of his vessel’s seaworthiness, Russell built on the work on Frege and Peano in an attempt to overcome Kant’s separation of math and logic. Russell searched for a reduction of all mathematical truth to formal logical deductions recently introduced by Boole in The Laws of Thought. Unfortunately, his inquiry discovered a leak in the naive set theory that held mathematics together. To plug this leak, he dedicated himself to writing along with his former supervisor Whitehead the Principia Mathematica and introducing the theory of types.
Among mathematicians and computer scientists, the Principia is probably Russell’s best known contribution. Not because he built a theory that was a useful way to think about sets (that honour went to Zermelo and Fraenkel), but because his presentation and associated philosophy was clear enough for others to meaningfully disagree. In the 30s, Gödel provided this disagreement and with his incompleteness theorems showed that the sort of solid formal logical hull that Russell was searching for does not exist; there is no unsinkable ship.
Given the violence Gödel’s results wrought to logicism, it might seem surprising how little Russell wrote about them. But this surprise is resolved because by the 30s that early Russell was long gone; exhausted by writing the Principia, and (more importantly) by the turmoil of the first Word War, Russell’s focus changed from the Pythagorian view of mathematics to the reality of human life around him. This middle Russell was optimistic, hopeful of reform and advances in education. For him, mathematics had become just a collection of tautologies “as trivial as the statement that a four-footed animal is an animal”. I believe this sentiment came from his struggle with dynamics versus statics. Although he was aware “of the substitution of dynamics for statics which began with Galileo, and which has increasingly affected all modern thinking, whatever scientific or political.” He was unwilling to let this dynamics penetrate into logic and mathematics where we can see through his provocative debates with Dewey that he still viewed Truth more fondly than Inquiry.
The onset of the Second World War marks, for me, the late Russell. He fully embraced change but replaced much of his middle optimism with caution and a hope that mankind avoids the most devastating follies possible with modern war. His critiques became more scathing and beautiful in their ironic play; he stressed the difference between change and progress, and the importance of science:
Our own planet, in which philosophers are apt to take a parochial and excessive interest, was once too hot to support life and will in time be too cold. After ages during which the earth produced harmless trilobites and butterflies, evolution progressed to the point at which it generated Neros, Genghis Khans, and Hitlers. This, however, is a passing nightmare; in time the earth will become again incapable of supporting life, and peace will return.
That summarize much of the hypocritical objectivity and false-detachment that I find in many scientists and science-lovers. Even in describing mere change, it is impossible to separate our ethics from our science, and to pretend otherwise is unproductive. No matter how much the cosmos inlittle us, and no matter how amoral and inhuman the universe is, it is still important to realize that in mere description and choice of subject, we introduce a human bias. To simply ignore this, can be dangerous.
Of course, to swing to the other extreme and to imagine our pleasures as somehow determining the universe is even more a threat. The threat of progress:
But this purposeless see-saw, which is all that science has to offer, has not satisfied the philosophers. They have professed to discover a formula of progress, showing that the world was becoming gradually more and more to their liking. The recipe for a philosophy of this type is simple. The philosopher first decides which are the features of the existing world that give him pleasure, and which are the features that give him pain. He then, by a careful selection among facts, persuades himself that the universe is subject to a general law leading to an increase of what he finds pleasant and a decrease of what he finds unpleasant.
Of course, when we hear “pleasant” we are eager to think that scientists are immune to this effect. Science is impersonal after all, and you need a person to be pleased. Unfortunately, science is a human affair and thus susceptible to pleasure. Without philosophical reflection, it is easy for us to believe that our observations are objective and our theories are approximations of some eternal truth. However, such a view can quickly lead to scientism and the establishment of dogma. If we focus only on the incremental development in our own little corner of thought, it is easy to succumb to the view that we have progressed. It is easy to jump from the reasonably established to the speculative and suppose that our speculations are not absurd. By studying philosophy, we can see how often certain thought proved wrong before, and how some of the things we believe to be established by science are actually artifacts of cultural or historic biases.
Whenever I am buried in the trenches of technical work, I find it important to occasionally take a breath, peer out, and ask myself: am I working on the right things? Am I aware of my assumptions? What prior work most closely resembles my own, and what have I changed? What is the current of thought are my assumptions in, and what are the main objections to this current?