Saturday, May 26, 2018

Philosophy of Science, or Philosophy vs Science?

A review of "Theory and Reality", by Peter Godfrey Smith, touching on a few criticisms and issues in the philosophy of science.

The philosophy "of" science has been fraught for decades, if not centuries. The usurpation of the theological explanation certainly rubbed many religious thinkers the wrong way, and modern philosophy has, perhaps unconsciously, carried on that rather adversarial tradition. A 2003 book by Stanford professor Peter G. Smith recounts the more recent back and forths in a judicious fashion. The modern story starts with the logical positivists of the inter-war Vienna Circle. They wanted to put science on a firmer footing by describing a logical basis for the scientific method. While scientists were groping in the dark, they, with their logical powers as philosophers, were going to straighten out the whole field. Never mind that, at the very same time, Gödel and others were showing that even logical systems have their limits, quite apart from the details of how they are applied to what we (so naively!) call reality.

A logical positivist.

The logical positivists were a little like the behaviorists- they tried their best to ignore invisible abstractions and hidden causes. They were obsessed by language and clarity, attempting to make of scientific language something purely empirical, linked at every point to directly observable entities and tests. This language was also supposed to be comprehensive and simple, hopefully mathematical in nature. And everything "scientific" would then end up being proven and lock-tight. However there were many problems, some inspired by the arch-skeptic, David Hume.

One was the problem of induction. While the sun has come up over 4 billion times, and reliably in our personal observation, there is still no guarantee that it will rise tomorrow. Such a prediction, premised on the inductive logic that since the sun has always come up, it will ever do so, can never be "proven". It can only be a matter of probability, confounded by the next black hole to come sailing through the solar system. The positivists and others trying to put the routine scientific logic of explanation and induction on a footing of certainty could not do so, however hard they tried. Even calling our most regular and elegant findings "natural laws" doesn't help. They remain founded on the clay of repeated observation and probabalistic extrapolation, not gold-plated logic (except for relations that are actually mathematical, like the symmetry laws of Emmy Noether; yet these rely on other observables for their premises, so ultimately rest on contingent properties of the universe). There was a sort of mathematics envy going on, as philosophers obsessed with making sense of physics yearned to make everything provable.

But that is not possible. Our findings about the world, however carefully observed, elegantly abstracted, and powerfully predictive, are necessarily probabilistic generalizations. Late in Smith's book, he delves into Bayesian logic and its stong attractions to philosophers as a way to represent probabilistic representations of the claims of science. Smith is dubious, and hopes for another solution, but it is important to point out that Bayes' theorem is not just a technical innovation to parameterize our belief and doubt. It is a solution for the whole problem of induction, which is to say that our expectations for certainty (whereby it is called inductive logic) need to be fundamentally tempered. An earlier breakthrough along these lines happened from Karl Popper, who offered disproof as the coin of the scientific realm. Perhaps, since nothing could be inductively proven, scientists could just work in disproving bad hypotheses, and leave it at that. But that is not how science works either. More on that below.

There were many other problems with the logical positivist program, such as an inability to make of language a pure, clean, perfectly observation-based mode of expression. No, languages of any kind presuppose large networks of meaning that have to be learned, and imply ontologies (unseen and abstract, no less) which model some version of reality, including hidden aspects. The whole positivist program is now a historical curiosity, (though its empiricist aspects are far from dead), but it paved the way for other, sometimes even more extreme approaches.

The most devastating critique was a social one. The 60's and 70's brought philosophers who looked more closely at what scientists did, and found that, far from following the dictates of the logical positivists, or at least those of Popper, they were behaving a lot like humans, with pet theories, a mania to prove themselves right, and petty squabbles over elaborate theories and the credit for them. Thomas Kuhn led the way, with an altogether nuanced and sophisticated picutre of the scientific process. Kuhn is probably the hero of Smith's book, and is rehabilitated in several respects. Kuhn devoted most of his main work to the process of "normal science", which goes forth within an over-arching paradigm that is largely uncontested, is inculcated by lengthy training (not to say indoctrination!), and digs ever deeper into the secrets of its field. Kuhn then followed with a description of the crisis phase of science. This is when paradigms change, and old verities no longer hold. He noted dryly that this is when scientists tend to become interested in philosophy! The clearest example is the quantum and relativistic revolutions in physics, which upended the stable, indeed Euclidean, Newtonian world.

To step out of the story briefly, it is imporatant to note here that, while Kuhn's story has given us the impression that such paradigm shifts are a necessary and continuing part of science, thus that nothing we know now is really stable or "true", that would be misleading. The Newtonian world lives on as a first approximation of reality- it was not discarded in any complete way. Equally important, some fields have really come to a final picture of their subjects. Molecular biology is an example. New things continue to be found and we have very far to go to unravel all the molecular networks that touch on health, not to mention consciousness, but the basic picture of DNA and its core processes are not going to change. Biology after Darwin could have been upended by the new technologies of genetics, microscopy, crystallography, and then of DNA. But it has not been- far from. Each innovation has only provided deeper and more detailed explanations of the theory of natural selection, in all its ramifications.

While Kuhn was very measured in his portrayal, his successors in social constructivist and postmodern philosophy let it all hang out, generating a decades-long body of work that, at its fringes, claimed that science was entirely socially constructed, and had no more say about the nature of reality than did the science of voodoo, which was at least the province of an oppressed and thus virtuous and authentic society. This fed on the age-old obsession of philosophy- what is reality? If observation is theory-driven, which everyone now agrees on, (in contrast to the logical positivists), how does reality enter our models of it? Obviously, there is a cycle (one might even call it a dialectic!) going on, of hypothesis, observation, evaluation, problem, and re-hypothesis. Our minds excel in making models, which then inform our observations, which then feed back (if we are paying attention) to those models. But a sufficiently motivated philosopher with a sufficiently narrow and uncharitable view of what is going on in science can come to a different conclusion. Smith provides a valedictory about this phase of his field:
"A lot of work in these fields has been organized around the desire to oppose a particular Bad View that is seen as completely wrong. The Bad View holds that reality determines thought by stamping itself on a passive mind; reality acts on scientific belief with 'unmediated compulsory force'. That picture is to be avoided at all costs; it is often seen as not only false but even politically harmful, because it suggests a passive, inactive view of human thought. Many traditional philosophical theories are interpreted as implicitly committed to this Bad View. This is one source for descriptions of logical positivism as reactionary, helpful to oppressors, and so on. 
What results from this is a tendency for people to go as far as possible away from the Bad View. This encourages people to asset simple reversals of the Bad View's realtionship between the mind and world. Thus we reach the idea that theories construct reality. 
Some explicitly embrace the idea of an 'inversion' of the traditional picture, while others leave things more ambiguous. But there is little pressure within the field [Science studies, particularly] to discourage people from going too far in these statements. Indeed, those who express more moderate denials of the Bad View leave themselves vulnerable to criticism from within the field. The result is a literature in which one error - the veiw that reality stamps itself on the passive mind - is exchanged for another error, the view that thought or theory constructs reality."

One author comes in for extra discussion- Paul Feyerabend:
 "Feyerabend was not, as he is sometimes portrayed, an 'enemy of science'. He was an enemy of some kinds of science. In the seventeenth century, according to Feyerabend, science was the friend of freedom and creativity, and was heroically opposed to the stultifying grip of the Catholic church. ... But the science of Galileo is nto the science of today. Science, for Feyerabend, has gone from being an ally of freedom to being an enemy. Scientists are turning into 'human ants', entirely unable to think outside of their training. And the dominance of science in society threatens to turn man into a 'miserable, unfriendly, self-righteous mechanism without charm or humor.' In the closing pages of Againt Method, he delcares that society now has to be freed from the strangling hold of a domineering scientific establishment, just as it once had to be freed from the grip of the One True Religion."

One can see how this ties in with the anti-intellectualism of the current Trumpian moment, and how the Evangelical movement sees its deepest interests in the construction and maintenance of an alternate reality that has been comprehensively threatened by intellect salvaged by a man like Trump, who shares their postmodern view about things like reality and its moral implications.

Smith spends the later parts of the book not on historical review, but on an effort to synthesize a more mature view of the field, taking a pluralistic view of what counts as evidence in science, and how the interaction with reality operates, ending up with a very reasonable view of the matter:

".. we might think of science as something like a strategy. In this sense science is the strategy of subjecting even the biggest theoretical ideas, questions, and disputes to testing by means of observation. This strategy is not dictated to us by the nature of human language, the fundamental rules of thought, or our biology; it is more like a choice. The choice can be made by an individual or a culture. The scientific strategy is to construe ideas, to embed them in surrounding frameworks, and to develop them, in such a way that exposure to experience is sought even in the case of the most general and ambitious hypotheses about the universe. That view of science is a kind of empiricism."

There are a couple more points that I would add to what Smith presents. First is about the role of criticism in science. This gets somewhat short shrift, I think, in favor of citation credit as the primary mode of motivation, yet plays a central role. Everyone is a critic- that is true in all walks of life and work. There is great power that accrues to scientists who brilliantly point out the flaws in others' work. This is why thesis committees exist, and peer review, grant review, group meetings, conferences, and much of the social apparatus of science, such as it is. Criticism, especially in public, inspires fear, which in turn inspires enormous efforts to address weaknesses in one's work. It is one of the primary motivations for scientists to make extra mental effort step outside their pet theories and obsessions- to strain to be "objective".

A second point is about another motivation in science, the ultimate one. This is not social at all, whether social approbation, credit, or fear, but is rather more spiritual: personal contact with reality. There really are eureka moments, in science as elsewhere, and they are tremendously fulfilling. All the care about details, the straining to be objective, and the acceptance of criticism, all function in the service of making contact with some new truth about the real world. Scientists are not Marines. They do not live and die for their band of brothers. They dedicate their lives to truth ... the pursuit we all share in some portion in our native curiosity to learn ever more about our world, but which, taken seriously, morally, and systematically, turns into the privilege of working full time to push forward knowledge about topics more or less obscure and useful, aka science.

It is an implicit recognition of the philosophical difficulties of dealing with and knowing about reality- this shadow world that we study incessantly, through our mental powers of modeling, but can never directly know. This is why students are given laboratory exercises, rote as they may be- to show that what seems so inert on the pages of their textbooks was once alive as a question which was answered by nature via a theory-driven and carefully constructed test. That the sought-after truth may be imperfect, tentative, and probabilistic is no matter. Any progress is better than none. And touching a new truth about how things work, which no one has witnessed before, after a lifetime spent feeding on the regurgitated knowledge of others, is truly addictive.

Smith's book finally shows a significant retreat from the glorious early aims of the queen of the sciences to rule over her dronish brethren. Philosophy may deal in big questions, but it is not very adept at answering them, or even posing them very constructively. Its lack of empirical engagement leaves it prone to the kind of appalling group-think that led the French constructivists and science studies acolytes so thoroughly off the rails. Its attitude towards science has been remarkably patronizing and counterproductive, not to say politicized and naive. Smith retreats to a far more humble descriptive, rather than normative, program of accepting pluralism in the methods and criteria of various sciences, and working, (one might say almost scientifically), to sort through and make sense of each of them in turn.

  • Errol Morris blames Kuhn for postmodernism and scientific faith-ism ... which is unfair.
  • Coming to terms with reality.
  • Trumpire Putinesca. "Sater is the one who famously sent Cohen the email in 2015 that said 'I will get Putin on this program, and we will get Donald elected.'"
  • Comey v McCabe.
  • Pigs on Twitter.

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