When is a consistent account in science good enough?

We often want our accounts in science to be consistent with the facts.  Even if we can't explain all the current facts, we can always hope to say, truthfully, that our knowledge is imperfect but our current theory is at least largely true....or something close to that....until some new 'paradigm' replaces it.

It is also only natural to sneer at our forebears' primitive ideas, of which we, naturally, now know much better.  Flat earth?  Garden of Eden?  Phlebotomy?  Phlogiston?  Four humors?  Prester John, the mysterious Eastern Emperoro who will come to our rescue?  I mean, really!  Who could ever have believed such nonsense?

Prester John to the rescue (from Br Library--see Wikipedia entry)

In fact, leaders among our forebears accepted these and much else like it, took them as real, sought them for solace from life's cares not just because they were promised (as in religious figures) but as earthly answers.  Or, to seem impressively knowledgeable, found arcane ways to say "I dunno" without admitting it.  And, similarly, many used ad hoc 'explanations' for personal gain--as self-proclaimed gurus, promisers of relief from life's sorrows or medical woes (usually, if you cross their palms with silver first).

Even in my lifetime in science, I've seen forced after-the-fact 'explanations' of facts, and the way a genuine new insight can show how wrong those explanations were, because the new insight accounts for them more naturally or in terms of some other new facts, forces, or ideas.  Continental drift was one that had just come along in my graduate school days.  Evolution, relativity, and quantum mechanics are archetypes of really new ideas that transformed how our forebears had explained what is now our field of endeavor.

Such lore, and our more broad lionizing of leading political, artistic or other similarly transformative figures, organizes how we think.  In many ways it gives us a mythology, or ethnology, that leads us to order success into a hierarchy of brilliant insights.  This, in turn, and in our careerist society, provides an image to yearn for, a paradigm to justify our jobs, indeed our lives, make them meaningful--make them important in some cosmic sense, and really worth living.

Indeed, even ordinary figures from our parents, to the police, generals, teachers, and politicians have various levels of aura as idols or savior figures, who provide comforting answers to life's discomfiting questions.  It is natural for those burdened by worrisome questions to seek soothing answers.

But of course, all is temporary (unless you believe in eternal heavenly bliss).  Even if we truly believe we've made transformative discoveries or something like that during our lives, we know all is eventually dust.  In the bluntest possible sense, we know that the Earth will some day destruct and all our atoms scatter to form other cosmic structures.

But we live here and now and perhaps because we know all is temporary, many want to get theirs now, and we all must get at least some now--a salary to put food on the table at the very least.  And in an imperfect and sometimes frightening world, we want the comfort of experts who promise relief from life's material ills as much as preachers promise ultimate relief.  This is the mystique often given to, or taken by, medical professionals and other authority figures.  This is what 'precision genomic medicine' was designed, consciously or possibly just otherwise, to serve.

And we are in the age of science, the one True field (we seem to claim) that delivers only objectively true goods; but are we really very different from those in similar positions of other sorts of lore?  Is 'omics any different from other omnibus beliefs-du-jour?  Or do today's various 'omical incantations and promises of perfection (called 'precision') reveal that we are, after all, even in the age of science, only human and not much different from our typically patronized benighted forebears?

Suppose we acknowledge that the latter is, at least to a considerable extent, part of our truth.  Is there a way that we can better use, or better allocate, resources to make them more objectively dedicated to solving the actually soluble problems of life--for the public everyday good, and perhaps less used, as from past to today, to guild the thrones of those making the promises of eternal bliss?

Or does sociology, of science or any other aspect of human life, tell us that this is, simply, the way things are?

Serial science

Are you hooked on Serial yet?  The current season of this radio series from the makers of This American Life explores whether Adnan Syed, in jail for the last 15 years and sentenced to life for killing his ex-girlfriend Hae Min Lee when they were both 18, really did it.  He says he didn't.  His friend Jay says he did.  The question comes down to, what happened in those crucial 21 minutes when his whereabouts are unknown and undocumented, and Hae was strangled?

Sarah Koenig, presenter of this series, and a producer of This American Life, describes herself as having been obsessed with this case for the past year.  She probes every angle, reads every report she can find, listens to the police interview tapes, talks to anyone who will speak to her about what they saw or what they know, revisits the supposed scene of the crime, tests whether Adnan could have gotten there in the 21 minute window of opportunity, challenges Adnan with her thoughts, doubts and questions in hundreds of phone calls, and so much more.

What she realized is that the trial covered up a far more complicated story, which neither the jury nor the public got to hear. The high school scene, the shifting statements to police, the prejudices, the sketchy alibis, the scant forensic evidence - all of it leads back to the most basic questions: How can you know a person’s character? How can you tell what they’re capable of? In Season One of Serial, she looks for answers.

Some weeks Koenig is convinced Adnan is guilty, some weeks she's not so sure. We don't yet know what she concludes, or indeed whether she concludes anything other than that it's impossible to reach a conclusion, but, perhaps because it's possible to weigh the evidence from various angles, it's a gripping series.

Scales of justice; Wikipedia

A compelling story.  Not because we really care about Adnan -- unless he's innocent, in which case of course, the injustice is a tragedy.  Indeed, it's Hae one really cares about, a bright young woman whose future was violently and callously taken from her.  And, the idea that, to compound this tragedy, a young man's life may have been ruined by a system that didn't do it's job is also part of the emotional hook that keeps us listening.  But more, to me the show is fascinating because of what it tells us about truth, and how we know what we know.

Starting with the Enlightenment around 400 years ago, the gold standard for science has been empirical evidence, the equivalent of fingerprints, witness stories and DNA.  Naturalists collected then, scientists collect now, observational or experimental data, to try to make sense of, and build a story with.  As Koenig does, scientists assume there's a truth, and that evidence can lead us to it.  Yes, the evidence needs to be tested and weighed, and evaluated and re-evaluated, but the assumption is that with evidence we can know the truth.

But that's science. Koenig is talking about a legal question -- this crime happened, who did it? Lawyers aren't necessarily looking for the truth, even though they know there is one, because they know they can't necessarily know what it is.  The evidence often can be interpreted in numerous ways, used by a canny defense attorney as well as a canny prosecutor in support of either guilt or innocence.  Or, as in Adnan Syed's case, it seems that what would be crucial evidence just doesn't exist, so he was convicted on circumstantial evidence instead.

And of course sometimes pieces of evidence are omitted in the pursuit of a consistent story, which is often what lawyers are really after.  Many times, defense lawyers don't know whether their client is guilty or innocent, but they simply (or not so simply) build whatever exculpatory story the evidence (or some of the evidence) will support.  So, Koenig is being an ace reporter in this series, and a great storyteller as she unpeels layer after layer after layer of evidence in her search for the truth, but she's not necessarily being a winning lawyer.  But that's ok; she is a reporter.  By contrast, in our system a lawyer's job is to take sides, not to seek truth, which is different from science and might seem strange unless you realize that there may not be a better way, to determine guilt or innocence  when truth can't be tested directly.

Chemical balance; Indica Scientific

Scientists are telling stories from evidence, too, with the hope that there's a knowable truth to be found.  As much evidence as they can get.  Should they be impartial?  Yes and no.  Building evidence is what the whole push for Big Data, and meta-analyses is about; building stories from enough data that we can assume we're approaching the truth.  Evidence that should be weighed impartially.  This seems like the new path to truth but, to be fair, Darwin collected Big Data in his way, too, observing more pigeons, barnacles, and orchids than most of us would have had the stomach for.  He was a diligent, patient observer, who also built a consistent story from the evidence -- but with various theories in mind.  Not impartially.  So, scientists are reporters of the natural world, but the synthesizer scientists are lawyers, too, piecing together the evidence to make a good, consistent story, taking a side.

But, it's never clear how close we are to the truth, even if or when we think we can assume there is a single truth.  Understanding what genes are and what they do, for example, took a lot of sleuthing, building a story, from the circumstantial evidence that Mendel so diligently provided, to the discovery that chromosomes were an important actor, and the discovery of DNA, and so on.

But geneticists understood what genes were a lot more definitively in the beginning than they do now. Ironically that was because it was before there was so much evidence.  Ask 5 of them now what a gene is, and if any of them actually give you an answer it will be vague, and it's likely that it won't agree with any of the others you get.  Ken always told his Human Genetics students each semester that much of what he was going to tell them wasn't going to be true the next year.  They seemed surprised or nonplussed, but he then explained about our growing knowledge and understanding.  Presumably there's a truth, and presumably we're heading toward it, but often it seems we have no idea how close we are getting to it.  Of course, the goal keeps changing as discoveries keep happening, and that doesn't help.

We don't yet know how Sarah Koenig is going to conclude her story.  She will have plowed through masses of evidence, but if the truth was in there to be found, I think it would have been found 15 years ago.  She's talking to a lot of people who knew Hae and know Adnan, and perhaps she'll dig up something new and significant that might change the story.  But so far, the crucial evidence is missing; only Adnan, Jay and Hae know what happened, but Hae can no longer speak, there were no witnesses, and Adnan and Jay are telling different stories.  Or, maybe someone else killed Hae.

This is an imperfect metaphor for science, of course, because no one person is holding out on us on whether there are multiverses, or dark matter, or something crucial missing from our understanding of biology, or even how antimalarials work.  But the elusiveness of these kinds of truths, the difficulty of interpreting the evidence and the idea that we might need to re-evaluate the data from time to time certainly pertain to science.

Is there truth? Does science find it?

I listened yesterday to the first installment of this seasons's BBC Radio 4 radio program, In Our Time. Happy it's back!  This episode discussed the life and work of the French Enlightenment-era genius and polymath, Blaise Pascal.

The Enlightenment period was an intellectual fervor that turned from authority to empiricism in the belief that understanding the real world comes from observation and empiricism, not just consulting authority (like the Bible or Aristotle).  Main names of that era include Galileo, Descartes, Newton, Bacon, and so on.  They all were part of the push to understand theories or laws of nature based on careful experiment and observation.

Blaise Pascal, 1623-1662

These thinkers, and others, rejected the notion that perfect truth could be seen in the classical or sacred texts, but that we could at least better understand the world through careful scientific methods.  But how 'better'?  Is there truth about the  world?  Does it follow universal regularities--laws of nature, as Newton and his intellectual descendants to the present day say--or not?  If so, the job of science was to identify and understand those laws.  But there is a further implication of that view: there must be a truth!

If truth exists, does science find it?
The popular idea about science is that it seeks the truth about physical nature and, for those not holding out for non-physical truth such as religion, even about the nature of 'mind'.  Perhaps the popular belief is that in many areas science has done its job already.  For most, however, science is seen as approaching better and better understanding of truth in various areas like physics, chemistry, geology, biology and others.  The idea is that truth exists and we approach it asymptotically, that is, gradually getting ever closer--even if we, as imperfect creatures, may never get 100% there.

Pascal calculator

Philosophers of science had a longstanding view that science works by gradually refining its insights with very focused methods that get closer and closer.  Yes, there may still be major or even transforming insights yet to come, and yes, we can't now know what they'll be.  Only when the next Newton, Einstein, Maxwell, or Darwin come along will some jump rather than gradual approach to truth occur.  Often we hear the phrase 'paradigm' to refer to the current theory, and 'paradigm shift' to such huge transformations of our view--such as when evolution replaced creationism: you can't look back, once you see the new view and realize that it is.....what?  'true'?  'better'?  more convincing or convenient?  more useful for engineering and business?

Blaise Pascal and others, apparently even Newton himself, did recognize that science wasn't necessarily approaching Truth.  Only God could know the truth and (according to many of them) so had we until the fall in the Garden of Eden.  Still, they felt we could approach truth, and many believed that mathematics was some ultimately true and consistent language for doing that.

In the mid-20th century Thomas Kuhn and others looked at science not as a purely objective path of a train moving to the station of Truth, but instead as a social phenomenon, a society of individuals who accept a given explanation (that's the 'paradigm') and press towards making that explanation fit ever more facts.  This might be seen as just a sociological analysis of the way science works. But Kuhn and others said that that is not correct!  Science is a social mechanism for what we accept as truth, but there is no way to say that we are approaching truth.  A paradigm can explain facts we care about today, but not things we're not even asking about.  Nor, since we don't actually know what the truth is (or if there is such a thing!), we can't say science is 'progressing' towards understanding it.  Science leads to better explanation or more accurate prediction or account of aspects we currently care about, but usually omits consideration of things not convenient or interesting--or issues that haven't yet arisen.

Many of our posts on MT are about the struggle to understand the world and the various sociological aspects about the claims, activities, and so on that characterize modern life and health sciences.   An important aspect of this is the notion of causation and whether it can ever be purely deterministic or, perhaps more perplexingly, can be truly probabilistic.  We use  probability and statistics routinely in science, for various reasons, but often implicitly explaining that this is because there are always measurement and other sources of error, or things too miniscule for us to identify perfectly, or that we have to collect incomplete samples and try to generalize from them to the whole in some way.

One truth?  Many?  None?
Still, do we believe that Nature has universal--truly universal, everywhere on earth and everywhere else--laws or truth that apply without exception?  Such truth would be deterministic--if you know a situation perfectly you can predict the future perfectly.  If so, we might expect that scientific methods will be truly be able to reveal that truth, at least asymptotically.

Or, if truth is that causation is probabilistic (as it seems to be in quantum mechanics as it's done today), there isn't one state of Nature but an array each with some probability of being observed.  Even there, we assume a fixed or deterministic distribution, or set, of those probabilities.  If that's a correct view, then science--if we do it right--should be able to asymptotically approach the true values of those probabilities.

Could it be that we're more fundamentally wrong?  Could Nature not have just one truth in a given area, nor a universal truth?  If that's so, how would we know?  How would we know how many truths there were, or when and where they applied?  Are they discrete--that is, does one truth stand alone relative to other truths about the same thing?  If so, where are they relative to each other: do truths overlap, or is one truth more dominant than another?   If these questions had specific answers, we might expect that science could asymptotically approach this set or distribution of truths.  It's weird, but theories such as multiverse or many-worlds cosmologies entertain such ideas and treat them quite seriously.  Can we, or should we, try to build such concepts into our daily scientific life?

Today,  scientists can excuse ourselves as still being in an infantile state of understanding Nature, and plead for further support by saying that complete truth has eluded us so far but, because it exists, it's important to continue to refine our asymptotic approach to it.  That is, the more work we do, the closer we get to complete understanding.

Pascal's answer was that in frustration we'll be driven ultimately to theological religion (Christianity, for him) as the only, or at least the safest, way to go. It that's what happens to science, it will be quite a surprise....even a paradigm shift!