Infinite horizons; or why I am optimistic about the future

The Doomsday Scenario, also known as the Copernican Principle, refers to a framework for thinking about the death of humanity. One can read all about it in a recent book by science writer William Poundstone. The principle was popularized mainly by the philosopher John Leslie and the physicist J. Richard Gott in the 1990s; since then variants of it have have been cropping up with increasing frequency, a frequency which seems to be roughly proportional to how much people worry about the world and its future.

The Copernican Principle simply states that the probability of us existing at a unique time in history is small because we are nothing special. We therefore must exist roughly close to half the period of our existence. Using Bayesian statistics and the known growth of population, Gott and others then calculated lower bounds for humanity’s future existence. Referring to the lower bound, their conclusion is that there is a 95% chance that humanity will go extinct in 9120 years.

The Doomsday Argument has sparked a lively debate on the fate of humanity and on different mechanisms by which the end will finally come. As far as I can tell, the argument is little more than inspired numerology and has little to do with any rigorous mathematics. But the psychological aspects of the argument are far more interesting than the mathematical ones; the arguments are interesting because they tell us that many people are thinking about the end of mankind, and that they are doing this because they are fundamentally pessimistic. This should be clear by how many people are now talking about how some combination of nuclear war, climate change and AI will doom us in the near future. I reject such grim prognostications because they are mostly compelled by psychological impressions rather than by any semblance of certainty.

A major reason why there is so much pessimism these days is because of what the great historian Barbara Tuchman once called ‘Tuchman’s Law’; Tuchman’s Law states that the impression that an event leaves in the minds of observers is proportional to its coverage in the newspapers. Tuchman said this in 1979, and it has become a truism today because of the Internet. The media is much more interested in reporting bad things that happened rather than good things that did not happen, so it’s easy to think that the world is getting worse every day. The explosion of social media and multiple news sources have amplified this sensationalism and selection bias by gargantuan proportions. As Tuchman said, even if you may be relentlessly reading about a troubling phenomenon like child kidnapping or mass shootings, it is exceedingly rare that you will come home on any given day having faced such calamities.

In this trivial sense I agree with Bill Gates, Hans Rosling, Steven Pinker and others who have written books describing how by almost every important parameter – for instance child mortality, women and minority rights, health status, poverty, political awareness, environmental improvement – the world of today is not just vastly better than that of yesterday but has been on a steep and steady curve of improvement since medieval times. One simply needs to pick up any well-regarded book on medieval history (Tuchman’s marvelous book “The Distant Mirror” describing the calamitous 14th century will do the job) to realize how present human populations almost seem to live on a different planet as far as quality of life is concerned. This does not refute the often uneven distribution of progress, nor thus it tell us that every improvement that we have seen is guaranteed, nor this it say we should rest on our laurels, but it does give us more than enough rational cause for optimism.

Sometimes the difference between optimism and pessimism is simply related to looking at the same data point in two different ways. For instance, take as a reference date the year that the US Supreme Court legalized same-sex marriage – 2015. Now go back a hundred years, to 1915. Even in the United States the world of individual rights was stunningly different from now. Women could not vote, immigration from non-European countries was strongly discouraged and restricted, racism against non-white people (and even some white people such as Catholics) was part of the fabric of American society, black people were actively getting lynched in the south and their civil rights were almost non-existent, abortion was illegal, gay people would not dream of coming out of the closet and anti-Semitism was not only rampant but institutionalized in places like Ivy League universities.

It is downright incredible that, only a hundred years later, every single one of these barriers had fallen. Not one or two or three, but every single one. I cannot see how this extraordinary reversal of discrimination and inequality cannot lead to soaring optimism about the future. Now, two people might look at this fact in two different ways. One might say, “It took 228 years since the writing of the US Constitution for these developments to transpire”, while another person might say, “It took only a hundred years from 1915 for these developments to transpire”. Which perspective do you choose since both are equally valid? I choose the latter, not only because it points to optimism for the future but to informed optimism. There has been a tremendous raising of moral consciousness about equal treatment of all kinds of groups in the last one hundred years, and if anything, the strong, unstoppable waves of progressivism on the Internet promise that this moral elevation will continue unabated. There are effectively zero chances that women or minorities will lose the vote for instance. The price of liberty is eternal vigilance, not eternal pessimism.

What about those four horsemen of the apocalypse, now compressed into the three horsemen comprising nuclear war, AI and climate change, that seem to loom large when it comes to a dim view of the future of humanity? I believe that as real as some of the fears from climate change, nuclear war and AI are, they are exaggerated and not likely to impact us the way we think.

First, climate change. There are many deleterious impacts of human beings on the environment, of which global warming is an important one and likely the most complicated to predict in its details. It is harder to predict phenomena like the absorption of carbon dioxide by the biosphere and the melting of glaciers based on computer models than it is to understand and act on phenomena like ocean acidification, deforestation, air pollution and strip mining. Sadly, discussions of these topics are often lost in the political din surrounding global warming. There is also insufficient enthusiasm for solutions such as nuclear energy and solar power that can make a real impact on energy usage and fossil fuel emissions. On the bright side, support for fighting climate change and environmental degradation is more vociferous than ever, and social media thankfully has played an important role in generating it. This support is similar to the support that early 20th century environmentalists lent to preventing creatures like the American buffalo and whales from going extinct. There are good reasons to think that whatever the real or perceived effects of climate change, it will not cease to be a publicly important issue in the future. But my optimism regarding climate change does not just come from the level of public engagement I see but from the ability of humans to cope; I am not saying that climate change will pose no problem, but that one way or another humans will find solutions to contain or even eliminate those problems. Humans survived the last ice age at dangerously low levels of population and technological capability compared to today, so there is little reason to think that we won’t be able to cope. Some people worry whether it is worth bequeathing the uncertain world of tomorrow to our children and grandchildren. My belief is that, considering the travails that humanity successfully faced in the last thousand years or so, our children and grandchildren will be more than competent to handle whatever problem they are handed by their predecessors and the planet.

Second, nuclear war. The world’s nuclear arsenals have posed a clear and present danger for years. However, deterrence – as fragile and fraught with near misses as it is – has ensured that no nuclear weapon has been exploded in anger for almost 75 years. This is an almost miraculous track record. Moreover, while the acquisition of dirty bombs or nuclear material by non state actors is a real concern, the global nuclear stockpile has been generally quite secure, and there are enough concerned experts who continue to monitor this situation. Since the end of the Cold War, both the United States and Russia have significantly reduced their stockpiles, although both countries should go to still lower numbers. The detonation of even a low yield nuclear weapon in a major city will be a great tragedy, but it will not have the same effects as the global thermonuclear war whose threat the world labored under for more than fifty years. In 1960, Herman Kahn wrote “On Thermonuclear War”, a controversial book that argued that even a major thermonuclear war would not mean the end of humanity as most people feared. Part of Kahn’s analysis included calculations on the number of deaths and part included historical evidence of human renewal and hope after major wars. While the book was morbid in many details, it did make the point that humanity is far more resilient than we think. Fortunately the scenarios that Kahn described never came to pass, and the risk of them happening even on a small scale are now far lower than they ever were.

Finally, AI seems to be perhaps the prime reason for the extinction of humanity that many world and business leaders and laymen fear. Early fears centered on the kind of killer robots that dotted the landscape of science fiction movies, but recent concerns have centered on machines gradually developing intelligence and humans gradually ceding authority to them. But most AI doomsday scenarios are speculative at best and contain a core of deep uncertainty. For instance, a famous argument made by Nick Bostrom described a scenario called the AI paperclip maximizer. The idea is that humanity creates an AI whose purpose is to create paperclips. The AI will gradually single-mindedly start making paperclips out of everything, consuming all natural resources and rendering the human race extinct. This kind of doomsday scenario has some important assumptions built into it, among which is the assumption that such an AI can actually exist and wouldn’t have a failsafe built into it. But the bigger question is regarding the AI’s intelligence: any kind of truly intelligent AI won’t spend its entire time making paperclips, while any kind of insufficiently intelligent AI will be easily controlled by human beings or at least live with them in some kind of harmony. I worry much less about a paperclip AI than I do about humans gradually ceding thinking to fleeting sources of entertainment like social media.

But the real problem with any kind of doomsday scenario involving AGI (artificial general intelligence) is that it simply underestimates what it would take for a machine to acquire true human-like cognitive capabilities. One of the best guides to thinking about exactly what it would take for AGI to somehow take over the world is the technologist Kevin Kelly. He gives three principal reasons for the unlikelihood of this happening: one, that intelligence is along many axes, and even very intelligent human beings are usually intelligent along a few; second, that intelligence is not just gained through thinking alone but through experimentation, and that experimentation slows down any impact that a super-intelligence might have; and three, that any kind of AGI scenario assumes that the relationship between humans and their creations would be intrinsically hostile and fixed. Almost all such assumptions about AGI are subject to doubt, and at least a few of the conditions that seem to be necessary for AGI to truly dominate humanity seem to be both rate-limiting and unlikely.

Ultimately, most doomsday scenarios are based on predicting the future, and prediction, as Niels Bohr famously said, is very difficult, especially concerning the future. The most important prediction about the future of humanity will probably be the one that we are not capable of making. But in the absence of accurate prediction about the future, we have the past. And while the past is never a certain guide to the future, the human past in particular shows a young species that is almost infinitely capable of adaptation, empathy, creativity and optimism. I see no reason to believe this will not continue to be the case.

First published on 3 Quarks Daily.

Kurt Gödel's Open World

Today marks Kurt Gödel's one hundred and eleventh birthday. Along with Aristotle, Gödel is often considered the greatest logician in history. But I believe his influence goes much farther. In an age when both science and politics seem to be riddled with an incessant search for "truth" - often truth that aligns with one's preconceived social or political opinions - Gödel's work is a useful antidote and a powerful reminder against the illusion of certainty.

Gödel was born in 1906 in Brünn, Czechoslovakia, at a time when the Austro-Hungarian empire was at its artistic, philosophical and scientific peak. Many of Gödel's contemporaries, including Ludwig Wittgenstein, distinguished themselves in the world of the intellect during this period. Gödel was born to middle class parents and imbibed the intellectual milieu of the times. It was an idyllic time, spent in cafes and lecture halls learning the latest theories in physics and mathematics and pondering the art of Klimt and the psychological theories of Freud. There had not been a major European conflict for almost a hundred years.

In his late teens Gödel came to Vienna and became part of the Vienna Circle, a group of intellectuals who met weekly to discuss the foundations of philosophy and science. The guiding principle of the circle was the philosophy of logical positivism which said that only statements about the natural world that can be verified should be accepted as true. The group was strongly influenced by both Bertrand Russell and Ludwig Wittgenstein, neither of whom was formally a member. The philosopher Karl Popper, whose thinking on falsification even now is an influential part of science, ran circles around the group, although his love for them seems to be unreciprocated.

It was at the tender age of 25 that young Gödel published his famous incompleteness theorem. He did this as part of his PhD dissertation, making that dissertation one of the most famous in history (as a rule, even most famous scientists don't always do groundbreaking work in graduate school). In a mere twenty-one pages, Gödel overturned the foundations of mathematics and created an edifice that sent out tendrils not just in mathematics but in the humanities, including psychology and philosophy.

To appreciate what Gödel did, it's useful to take a look at what leading mathematicians thought about mathematics until that time. Both Bertrand Russell and the great mathematician David Hilbert had pursued the foundations of mathematics with conviction. In a famous address given in 1900, Hilbert had laid out what he thought were the outstanding problems in mathematics. Perhaps none of these was as important as the overarching goal of proving that mathematics was both consistent and complete. Consistency means that there exists no statement in mathematics that is both true and false at the same time. Completeness means that mathematics should be capable of proving the truth or falsity (the "truth value") of every single statement that it can possibly make. 

In some sense, what Hilbert was seeking was a complete "axiomatization" of mathematics. In a perfectly axiomatized mathematical system, you would start with a few statements that would be taken as true, and beginning with these statements, you would essentially have an algorithm that would allow you derive every possible statement in the system, along with their truth value. The axiomatization of mathematics was not a new concept; it had been pioneered by Euclid in his famous text of geometry, "The Elements". But Hilbert wanted to do this for all of mathematics. Bertrand Russell had similar dreams.

In one fell swoop the 25-year-old Gödel shattered this fond hope. His first incompleteness theorem, which is the most well-known, proved that any mathematical system which is capable of proving the basic theorems of arithmetic is always going to include statements whose truth value cannot be proved using the axioms of the system. You could always 'enlarge' the system and prove the truth value in the new system, but then the new, enlarged system itself would contain statements which succumbed to Gödel's theorem. What Gödel thus showed is that mathematics will always be undecidable. It was a remarkable result, one of the deepest in the annals of pure thought, striking at the heart of the beautiful foundation built by mathematicians ranging from Euclid to Riemann over the previous two thousand years.

Gödel's theorems had very far-reaching implications; in mathematics, in philosophy and in human thought in general. One of those momentous implications was worked out by Alan Turing when he proved a similar theorem for computers, addressing a problem called the "halting problem". Similar to Hilbert's hope for the axiomatization of mathematics, the hope for computation was that, given an input and a computer program, you could always find out whether the program would halt. Turing proved that you could not decide this for an arbitrary program and an arbitrary input (although you can certainly do this for specific programs). In the process Turing also clarified our definitions of "computer" and "algorithm" and came up with a universal "Turing machine" which embodies a mathematical model of computation. Gödel's theorems were thus what inspired Turing's pioneering work on the foundations of computer science.

Like many mathematicians who make seminal contributions in their twenties, Gödel produced nothing of comparable value later in his life. He migrated to the US in the 1930s and settled down at the Institute for Advanced Study in Princeton. There he made a new friend - Albert Einstein. From then until Einstein's death in 1955, the sight of the two walking from their homes to the institute and back, often mumbling in German, became a town fixture. Einstein afforded the privilege of being his walking companion to no one, and seemed to have considered only Gödel as his intellectual equal: in fact he held Gödel in such esteem that he was known to have said in his later years that his own work did not mean much to him, and the main reason he went to work was to have the privilege of walking home with Gödel. At least once Gödel startled his friend with a scientific insight he had: he showed using Einstein's own field equations of gravitation that time travel could be possible.

Sadly, like a few other mathematical geniuses, Gödel was also riddled with mental health problems and idiosyncrasies that got worse as he grew older. He famously tried to find holes in the U.S. Constitution while taking his citizenship exam, and Einstein who accompanied him to the exam had to talk him out of trying to demonstrate to the judge how the U.S. could be turned into a dictatorship (nowadays some people have similar fears, but for different reasons). After Einstein died Gödel lost his one friend in the institute. Since early childhood he had always been a hypochondriac - often he could be seen dressed in a warm sweater and scarf even in the balmy Princeton summer - and now his paranoia about his health greatly grew. He started suspecting that his food was poisoned, and refused to accept anything not cooked by his protective wife Adele; in 1930s Vienna she had once physically protected him from Nazis, and now she was protecting him from imagined germs. When Adele was hospitalized with an illness, Kurt stopped eating completely. All attempts to soothe his fears failed, and on January 14, 1978 he died in Princeton Hospital, weighing only 65 pounds and essentially succumbing to starvation. Somehow this sublimely rational, austere man had fallen prey to a messy, frightful, irrational paranoia; how these two contradictory aspects of his faculties conspired to doom him is a conundrum that will remain undecidable.

He left us a powerful legacy. What Gödel's theorems demonstrated was that not only the world of fickle human beings but also the world of supposedly crystal-clear mathematics is, in a very deep sense, unknowable and inexhaustible. Along with Heisenberg's uncertainty principle, Gödel's theorems showed us that all attempts at grasping ultimate truths are bound to fail. More than almost anyone else, Gödel contributed to the fall of man from his privileged, all-knowing position.

We see his undecidability in politics and human affairs, but it is true even in the world of numbers and watertight theorems. Sadly we seem to have accepted uncertainty in mathematics while we keep on denying it in our own lives. From political demagogues to ordinary people, the world keeps getting ensnared in passionate attempts to capture and declare absolute truth. The fact that even mathematics cannot achieve this goal should give us pause. It should inculcate a sense of wonder and humility in the face of our own fallibility, and should lead us to revel in the basic undecidability of an open world, a world without end, Kurt Gödel's world. 

The data junkie and the lamp post: Cancer, genomics and technological solutionism

The Cancer Genome Atlas

The other day I was having a nice discussion with a very knowledgable colleague about advances in genomic sequencing and how they are poised to transform the way we acquire and process genetic information in biology, biochemistry and medicine. The specific topic under consideration was the bevy of sequencing companies who are showcasing their wares at the Advances in Genome Biology and Technology 2015 conference. Many companies like Solexa and Oxford Nanopore are in an intense race to prove whose sequencing technology can become the next Illumina, and it's clear that much fame and fortune lies ahead for whoever gets there first. It's undoubtedly true that technological developments in this field are going to have enormous and uncertain ramifications for all kinds of disciplines as well as potentially for our way of life.

And yet as I mull over these issues I am reminded of an article by MIT biologist Michael Yaffe from the journal Science Signaling which warns against the quick wielding of what the philosopher of technology Yevgeny Morozov has called “technological solutionism”. Technological solutionism is the tendency to define problems primarily or purely based on whether or not a certain technology can address them. This is a concerning trend since it foreshadows a future where problems are no longer prioritized by their social or political importance but instead by how easily they would succumb under the blade of well-defined and easily available technological solutions. Morozov’s solutionism is a more sophisticated version of the adage about everything looking like a nail when you have a hammer. But it’s all too real in this age of accelerated technological development, when technology advances much faster than we can catch up with its implications. It’s a problem that only threatens to grow.

In his piece Yaffe alerts us to the pitfalls of somewhat mindlessly applying genomic sequencing to discovering the basis and cure for cancer and succumbing to such solutionism in the process. One of the great medical breakthroughs of the twentieth century was the finding that cancer is in its heart and soul a genetic disease. This finding was greatly bolstered by the discovery of specific genes (oncogenes and tumor suppressor genes) which when mutated greatly increase the probability and progress of the disease. The availability of cheap sequencing techniques in the latter half of the century gave scientists and doctors what seemed to be a revolutionary tool for getting to the root of the genetic basis of cancer. Starting with the great success of the human genome project, it became increasingly easier to sequence entire genomes of cancer patients to discover the mutations that cause the disease. Scientists have been hopeful since then that sequencing cancer cells from hundreds of patients would enable them to discover new mutations which in turn would point to new potential therapies.

But as Yaffe points out, this approach has often ended up relegating true insights into cancer to the application of one specific technology – that of genomics – to probe the complexities of the diseases. And as he says, this is exactly like the drunk looking under the lamppost, not because that’s where his keys really are but that’s where the light is. In this case the real basis for cancer therapy constitutes the keys, sequencing is the light. During the last few years there have been several significant studies on major cancers like breast, colorectal and ovarian cancer which have sought to sequence cancer cells from hundreds of patients. This information has been incorporated into The Cancer Genome Atlas, an ambitious effort to chart and catalog all the significant mutations that every important cancer can possibly accrue.

But these efforts have largely ended up finding more of the same. The Cancer Genome Atlas is a very significant repository, but it may end up accumulating data that’s irrelevant for actually understanding or curing cancer. Yaffe acknowledges this fact and expresses thoughtful concerns about the further expenditure of funds and effort on massive cancer genome sequencing at the expense of other potentially valuable projects.

So far, the results have been pretty disappointing. Various studies on common human tumors, many under the auspices of The Cancer Genome Atlas (TCGA), have demonstrated that essentially all, or nearly all, of the mutated genes and key pathways that are altered in cancer were already known…Despite the U.S. National Institutes of Health (NIH) spending over a quarter of a billion dollars (and all of the R01 grants that are consequently not funded to pay for this) and the massive data collection efforts, so far we have learned little regarding cancer treatment that we did not already know. Now, NIH plans to spend millions of dollars to massively sequence huge numbers of mouse tumors!

It’s pretty clear that while there has been valuable data gathered from sequencing these patients, almost none of it has led to novel insights. Why, then, do the NIH and researchers continue to focus on raw, naked sequencing? Enter the data junkie and the lamppost:

I believe the answer is quite simple: We biomedical scientists are addicted to data, like alcoholics are addicted to cheap booze. As in the old joke about the drunk looking under the lamppost for his lost wallet, biomedical scientists tend to look under the sequencing lamppost where the “light is brightest”—that is, where the most data can be obtained as quickly as possible. Like data junkies, we continue to look to genome sequencing when the really clinically useful information may lie someplace else.

The term “data junkie” conjures up images of the quintessential chronically starved, slightly bug-eyed nerd hungry for data who does not quite realize the implications or the wisdom of simply churning information out from his fancy sequencing machines and computer algorithms. The analogy would have more than a shred of truth to it since it speaks to something all of us are in danger of becoming; data enthusiasts who generate information simply because they can. This would be technological solutionism writ large; turn every cancer research and therapeutics problem into a sequencing problem because that’s what we can do cheaply and easily.

Clearly this is not a feasible approach if we want to generate real insights into cancer behavior. Sequencing will undoubtedly continue to be an indispensable tool but as Yaffe points out, the real action takes place at the level of proteins, in the intricacies of the signaling pathways involving hundreds of protein hubs whose perturbation is key to a cancer cell’s survival. When drugs kill cancer cells they don’t target genes, they directly target proteins. Yaffe mentions several recent therapeutic discoveries which were found not by sequencing but by looking at the chemical reactions taking place in cancer cells and targeting their sources and products; essentially by adopting a protein-centric approach instead of a gene-centric one. Perhaps we should re-route some of those resources which we are using for sequencing into studying these signaling proteins and their interdependencies:

These therapeutic successes may have come even faster, and the drugs may be more effectively used in the future, if cancer research focuses on network-wide signaling analysis in human tumors (20), particularly when coupled with insights that the TCGA sequencing data now provide Currently, signaling measurements are hard, not particularly suited for high-throughput methods, and not yet optimized for use in clinical samples. Why not invest in developing and using technologies for these signaling directed studies?

In other words, why not ask the drunk to buy a lamp and install it in another part of town where his keys are more likely to located? It’s a cogent recommendation. But it’s important not to lose sight of the larger implications of Yaffe’s appeal to explore alternative paradigms for finding effective cures for cancers. In one sense he is directly speaking to the love affair with data and new technology that seems to be increasingly infecting the minds and hearts of the new generation. Whether it’s cancer researchers hoping that sequencing will lead to breakthroughs or political commentators hoping that Twitter and Facebook will help bring democracy in the Arab world, we are all in danger of being sucked into the torrent of technological solutionism. Of this we must be eternally vigilant.

Adapted from a previous post on Scientific American Blogs.

Boundary value conditions, domain applicability and "American Sniper"

Actor Bradley Cooper in "American Sniper"

General relativity is a generalization of Newtonian mechanics which applies to large objects moving at high speeds that curve spacetime. Similarity, quantum mechanics is a generalization of classical mechanics which applies to very small objects like electrons and photons. Newtonian mechanics thus has a domain of applicability within which it works perfectly well even if it fails to work under the larger rubric of Einsteinian general relativity. Similarly classical mechanics has a domain of applicability within which it is golden. Both are perfectly comfortable within their own boundary value conditions - medium-sized objects and slow speeds for instance.

If you think about it, morality has similar domains of applicability. I was reminded of this comparison when I watched the Clint Eastwood-directed movie "American Sniper" over the weekend. The movie is about Chris Kyle, a celebrated US Navy sniper who over his four tours of duty in Iraq racked up 160 confirmed kills. The film has garnered some controversy for its supposed glorification of war and mindless patriotism. Kyle faced some gut-wrenching decisions in his sniper career in gunning down women and children who were enemy combatants, but by most accounts the decisions were quite simple for him and his conscience seemed clear. Personally, irrespective of where my political sympathies lie, I thought the movie was very gripping and well-made and enjoyed it, and Bradley Cooper was a revelation. After it ended I witnessed a kind of sustained and erie silence as the audience shuffled out of the theater, a silence that I haven't encountered very frequently before.

Since the audience was based in Boston, MA, it is unlikely that the silence was the result of them being enamored and stunned by Chris Kyle's sacrifice and patriotism. Instead I would like to think that the contemplative pause was provoked by a classic and highly problematic dilemma that mankind has faced since it acquired the ability to wage war: how can you vigorously oppose what you think is a highly unnecessary and immoral war and yet support the actions and decisions of individual soldiers like Chris Kyle who are putting their lives on the line with courage? It's a question Americans of every stripe face: when a soldier appears at the airport after returning from a tour, do you condemn him or her or laud their courage?

It's a very difficult question to answer, one whose answer is certainly not black and white and which we will almost certainly never definitively figure out in the foreseeable future. But a comparison with theories in science and especially in physics at least provides an interesting analysis in my opinion.

Here's the point: When Chris Kyle was looking down the barrel of his sniper rifle and had to pick between the life of a ten year-old Iraqi kid carrying a grenade and the life of five American marines, he picked the marines. The choice still wasn't easy but it was the best one to make under the limited parameters and boundary value conditions that he was operating under. The parameters were related to choosing between culpable Iraqi lives and American lives. The boundary value conditions had to do with the narrowly defined parameters of his mission or assignment. You could convince yourself that he had the right solution under those conditions even if you vehemently protested the war at large.

The fact of the matter is that moral decisions, as hard and endlessly unanswerable as they may be, still often operate within a limited domain of applicability. These domains of applicability have announced themselves in every war from the Mexican war to Vietnam. You can be for or against the moral decisions with some degree of confidence within those particular domains, even if you may be entirely opposed or in favor of them when the domains expand. It's like being in favor of Newtonian mechanics when you want to send rockets to the moon while being vehemently opposed to it when you want to send rockets to a neighboring galaxy containing black holes. Or like being in favor of classical mechanics when you want to deal with large blocks of gold while denying the use of that domain of applicability while analyzing individual gold atoms and the energy levels of their electrons. You can therefore potentially consider the political leaders who orchestrated the Iraq war to be war criminals even if you agree with the difficult decisions that Kyle made in those few seconds when he was looking down that gun barrel in Fallujah. 

There may be no answer to moral questions like those surrounding the Iraq war, and it is very likely that we may be forever divided into black and white bins when it comes to answering those questions. But I would like to believe that by dividing the conundrums into domains of applicability and at least agreeing that one's answer may depend on the exact boundary value conditions that one is dealing with, we may possibly reach a consensus and reach out into that gray area that always bedevils the gut-wrenching implications of our morality in both war and peace. Perhaps then we can meet halfway across and reach some kind of consensus, even if that consensus may be occupying the kind of twilight netherworld that entangled electrons do.

Philosophy begins where physics ends, and physics begins where philosophy ends

Richard Feynman - philosopher (Image:WashU)

A few months ago, physicist Sean Carroll has some words of wisdom for physicists who might have less than complimentary things to say about philosophy. The most recent altercation between a physicist and philosophy came from Neil deGrasse Tyson who casually disparaged philosophy in a Q&A session, saying that it can be a time sink and it doesn’t actually provide any concrete answers to scientific questions. Now I am willing to give Tyson the benefit of doubt since his comment was probably a throwaway remark; plus it’s always easy for scientists to take potshots at philosophers in a friendly sort of way, much like the Yale football team would take potshots at its Harvard counterpart.

But Tyson’s response was only the latest in a series of run-ins that the two disciplines have had over the past few years. For instance in 2012 philosopher David Albert castigated physicist Lawrence Krauss for purportedly claiming in his most recent book that physics had settled or at least given plausible answers to the fundamental question of existence. In reply Krauss called Albert “moronic” which didn’t help much to bridge the divide between the two fields. Stephen Hawking also had some harsh words for philosophers, saying that he thought “philosophy is dead”, and going further back, Richard Feynman was famously disdainful of philosophy which he called “dopey”.

In his post Carroll essentially deconstructs the three major criticisms of philosophy seen among physicists: there’s the argument that philosophers don’t really gather data or do experiments, there’s the argument that practicing physicists don’t really use any philosophy in their work, and there’s the refrain that philosophers concern themselves too much with unobservables. Carroll calls the first of these arguments dopey (providing a fitting rejoinder to Feynman), the second frustratingly annoying and the third deeply depressing.

I tend to agree with his take, and I have always had trouble understanding why otherwise smart physicists like Tyson or Hawking seem to neglect both the rich history of interaction between physics and philosophy as well as the fact that they are unconsciously doing philosophy even when they are doing science. For instance, what exactly was the philosophy-hating Feynman talking about when he gave the eloquent Messenger Lectures that became “The Character of Physical Law“? Feynman was talking about the virtues of science, about the methodology of science, about the imperfect march of science toward the truth; in other words he was talking about what most of us would call “the philosophy of science”. There’s also more than a few examples of what could fairly be called philosophical musings even in the technical “Feynman Lectures on Physics”. Even Tyson, when he was talking about the multiverse and quantum entanglement in “Cosmos” was talking philosophically.

I think at least part of the problem here comes from semantics. Most physicists don’t explicitly try to falsify their hypotheses or apply positive heuristics or keep on looking for paradigms shifts in their daily work, but they are doing this unconsciously all the time. In many ways philosophy is simply a kind of meta, higher level look at the way science is done. Now sometimes philosophers of science are guilty of thinking that science in fact fits the simple definitions engendered by this meta level look, but that does not mean these frameworks are completely inapplicable to science, even if they may be messier than what they appear on paper. It’s a bit like saying that Newton’s laws are irrelevant to entities like black holes and chaotic systems because they lose their simple formulations in these domains.

My take on philosophy and physics is very simple: Philosophy begins where physics ends, and physics begins where philosophy ends. And I believe this applies to all of science.

I think there are plenty of episodes in the history of science that support this view. When science was still in a primitive state, almost all musings about it came first from Greek philosophers and later from Asian, Arab and European thinkers who were called “natural philosophers” for a reason. Anyone who contemplated the nature of earthly forces, wondered what the stars were made up of, thought about whether living things change or are always constant or pondered if there is life after death was doing philosophy. But he or she was also squarely thinking about science since we know for a fact that science has been able to answer these philosophical questions in the ensuing five hundred years. In this case philosophy stepped in where the era’s best science ended, and then science again stepped in when it had the capacity to answer these philosophical questions.

As another example, consider the deep philosophical questions about quantum mechanics pondered by the founders of quantum mechanics, profound thinkers like Bohr, Einstein and Heisenberg. These men were brilliant scientists but they were also bona fide philosophers; Heisenberg even wrote a readable book called “Physics and Philosophy“. But the reason why they were philosophers almost by default is because they understood that quantum mechanics was forcing a rethinking about the nature of reality itself that challenged our notions not just about concrete entities like electrons and photons but also about more ethereal ones like consciousness, objectivity and perception. Bohr and Heisenberg realized that they simply could not talk about these far flung implications of physics without speaking philosophically. In fact some of the most philosophical issues that they debated, such as quantum entanglement, were later validated through hard scientific experiments; thus, if nothing else, their philosophical arguments helped keep these important issues alive. Even among the postwar breed of physicists (many of whom were of the philosophy-averse, “shut up and calculate” type) there were prominent philosophers like John Wheeler and David Bohm, and they again realized the value of philosophy not as a tool for calculation or measurement but simply as a guide to thinking about hazy issues at the frontiers of science. In some sense it’s a good sign then when you start talking philosophically about a scientific issue; it means you are really at the cutting edge.

The fact of the matter – and a paradox of sorts – is that science grows fastest at its fringes, but it’s also at the fringes that it is most uncertain and unable to reach concrete conclusions. That is where philosophy steps in. You can think of philosophy as a kind of stand-in that’s exploring the farthest reaches of scientific thinking while science is maturing and retooling itself to understand the nature of reality. Tyson, Hawking, Krauss, and in fact all of us, are philosophers in that respect, and we should all feel the wiser for it.

First published on SciAmBlogs.