Late Night Thoughts on Being

We live at a moment of embarrassing riches.  I won’t try to catalog our blessings, but I will point out one particular blessing.  Someone who wants to think and knows how can find a lot of new ways to think about interesting things, just a few key strokes away.  Three online journals deliver bite sized brilliance for free: Aeon, This View of Life, and Nautilus.  All three feature consistently provocative, thoughtful, well written, articles that are easily accessible to anyone well-informed enough to be interested. 

I have been feasting on the third tonight.  Chip Rowe lists the “Top 10 Design Flaws in the Human Body.”  These design flaws count, in my view, as some of the strongest pieces of evidence for human evolution.  Take number one, for example.  The human spine, with its double curve, puts a ridiculous amount of stress on the lower back.  My beagle’s spine, by contrast, seems perfectly engineered: a curve that distributes weight evenly between two sets of limbs.  Of course, that was the cost of freeing our forelimbs to do such tasks as checking our Facebook pages.  Rowe’s opening sentences express what is marvelous about these new journals.

The Greeks were obsessed with the mathematically perfect body. But unfortunately for anyone chasing that ideal, we were designed not by Pygmalion, the mythical sculptor who carved a flawless woman, but by MacGyver. 

Yes.  The sculptor begins with a hunk of material but designs from scratch.  MacGyver has to work with what he has and can exploit but is limited by the design already present in whatever he can pull out of the crashed plane.  Like MacGyver, natural selection must rig solutions to present problems.  If you wanted to design a bipedal spine from scratch, maybe you could get perfection.  If you have to start with a quadruped and raise it off the ground, then compromises are inevitable. 

On a level closer to the metaphysical marrow, Gregory Laughlin asks “Can a Living Creature Be as Big as a Galaxy?” 

William S. Burroughs, in his novel The Ticket That Exploded, imagined that beneath a planetary surface, lies “a vast mineral consciousness near absolute zero thinking in slow formations of crystal.” 

As it happens, I have been reading William S. Burroughs lately‑his letters and his novels Naked Lunch (like Moby Dick, an almost impossible read) and Junky (so good you won’t need heroin).  Laughlin thinks Burroughs is onto something.  Consider the speed of thought. 

The speed of neural transmissions is about 300 kilometers per hour, implying that the signal crossing time in a human brain is about 1 millisecond. A human lifetime, then, comprises 2 trillion message-crossing times (and each crossing time is effectively amplified by rich, massively parallelized computational structuring). If both our brains and our neurons were 10 times bigger, and our lifespans and neural signaling speeds were unchanged, we’d have 10 times fewer thoughts during our lifetimes. 

This explains what happened to the Amazing Colossal Man. 

If our brains grew enormously to say, the size of our solar system, and featured speed-of-light signaling, the same number of message crossings would require more than the entire current age of the universe, leaving no time for evolution to work its course.

Maybe our brain size, like Baby Bear’s porridge, is just right: bigger than a chimp but small enough to efficiently cohere. 

It may be that human brains specifically and living organisms generally must occupy a particular niche in the scale of physics.  Allison Eck puts the general point in “How Do You Say “Life” in Physics?”

The arrow of time points in the direction of disorder. The arrow of life, however, points the opposite way. From a simple, dull seed grows an intricately structured flower, and from the lifeless Earth, forests and jungles. How is it that the rules governing those atoms we call “life” could be so drastically different from those that govern the rest of the atoms in the universe?

In 1944, physicist Erwin Schrödinger tackled this question in a little book called What is Life?. He recognized that living organisms, unlike a gas in a box, are open systems. That is, they admit the transfer of energy between themselves and a larger environment. Even as life maintains its internal order, its loss of heat to the environment allows the universe to experience an overall increase in entropy (or disorder) in accordance with the second law.

I was insufficiently amazed by Erwin Schrödinger’s book when first I read it many years ago. 

Schrödinger pointed to a second mystery. The mechanism that gives rise to the arrow of time, he said, cannot be the same mechanism that gives rise to the arrow of life. Time’s arrow arises from the statistics of large numbers—when you have enough atoms milling about, there are simply so many more disordered configurations than ordered ones that the chance of their stumbling into a more ordered state is nil. But when it comes to life, order and irreversibility must reign even at the microscopic scale, with far fewer atoms in play. At this scale, atoms don’t come in large enough numbers for their statistics to yield regularities like the second law. A nucleotide—the building block of RNA and DNA, the basic components of life—is, for example, made of just 30 atoms. And yet, Schrödinger noted, genetic codes hold up impossibly well, sometimes over millions of generations, “with a durability or permanence that borders upon the miraculous.”

Living organisms are dependent upon physical processes that are small enough that they are not subject to the laws of averages.  This sequestering from larger physical processes is the first sequestering.  Before life could begin, there had to be a small space for it to begin.  Once it does begin, it sequesters itself in successively more effective ways.

But what can account for the “arrow of life”, that is, the direction of organic processes towards greater order (less entropy)?  Well, I guess I’ll blog on that tomorrow.  

Defending the Humanities

It is generally agreed that the humanities are in crisis.  James McWilliams sums up the evidence at The Hedgehog Review. 

Nationally, the number of students majoring in the humanities has fallen substantially since 1970.5 At Stanford, 45 percent of the faculty is trained in the humanities, but only 15 percent of students major in humanities fields.6 At Yale, between 1971 and 2013 the proportion of humanities majors dropped from 53 percent to 25 percent among women, and from 37 percent to 21 percent among men. Meanwhile, economics has skyrocketed as a preferred major, with the number of economics majors growing almost threefold at traditionally humanities-inclined institutions such as Brown University.7 The acronym STEM—science, technology, engineering, mathematics—is now part of every university’s lingua franca.

I have read a lot of pieces recently that defended the value of the humanities and found them all reasonably convincing to someone who values the humanities.  That was good enough over the last two or three centuries, during which time the universities did the work that was once done by the Church: deciding what was worthy thinking about.  The authority of universities has been eroded by a number of factors, but the most important is the pressure from two directions: outside support (donors and state legislatures) and the market for students. 

I am pretty sure I know how not to defend the humanities in this situation.  One should not argue, as McWilliams does, for the value of not knowing everything.  He is worried in particular about the value of not knowing how the brain produces consciousness.  If we did know, he supposes, the humanities would lose all purpose.  

Knowing that there are things we don’t know—and may never know—has a humbling effect on the human mind. Humility is a form of modesty that asks us to accept ambiguity. Ambiguity, in turn, is ultimately what brings us together to explore the mysteries of existence through the wonder-driven endeavors we lump under that broad umbrella known as the humanities. If we knew it all, if we understood what it was like to be a bat, probably even Logan Sander would not be a comparative literature major.

In a way, to catch consciousness, to close the mind-body gap, would be to eliminate that humility. It would be to answer most of the big questions—to collapse the umbrella and move into a post-human world. And that might sound great to logical positivists and atheists and neurobiologists. But as the essayist Charles D’Ambrosio reminds us, “Answers are the end of speech, not the beginning.”

I share McWilliams’ concern for humility; however, the “STEM” disciplines are quite capable of humiliating themselves.  All one has to do is consider the recent epidemic of scientific scandals and the never ending number of cases where some very well-known scientific fact (dietary cholesterol is bad) turn out to be blunders.  Science doesn’t need Shakespeare for that. 

If the humanities are to survive in a STEM heavy environment, it won’t be by building walls between the physical brain and consciousness.  It won’t be by teaching people to value dumbstruck awe more than the thrill of aha!  It will be by philosophers and other readers engaging with the best science available. 

Allow me to demonstrate.  In a marvelous piece at Aeon, “Last hominin standing,” Dan Falk opens with a fundamental question.

In the movie Sliding Doors (1998), a woman named Helen, played by Gwyneth Paltrow, rushes to catch a train on the London Underground, but just misses it, watching helplessly from the platform as the doors slide shut. The film explores two alternative universes, comparing the missed-train universe to a parallel reality in which she caught the train just in time. It wasn’t a cinematic masterpiece but it vividly confronts a question that many of us have asked at one time or another: if events had unfolded slightly differently, what would the world be like?

This question, applied to the history of life on our planet, has long beguiled thinkers of all stripes. Was the appearance of intelligent life an evolutionary fluke, or was it inevitable? This was one of the central themes in Stephen Jay Gould’s book, Wonderful Life: The Burgess Shale and the Nature of History (1989). If we re-played the tape of evolution, so to speak, would Homo sapiens – or something like it – arise once again, or was humanity’s emergence contingent on a highly improbable set of circumstances?

Falk, author of The Science of Shakespeare, begins with a bit of movie criticism and moves quickly to grand evolutionary theory.  Everyday human drama and the most profound questions about the earth and the kosmos are not found in separate realms; they are, as every Zen master will tell you, the same things. 

Falk pits Gould against Simon Conway Morris.  

To Gould, the late Harvard paleontologist, evolution was deeply contingent, an endless series of fluke events, the biological equivalent of just-caught and just-missed subway trains. By contrast, Conway Morris, a professor of paleobiology at the University of Cambridge, focused on convergence: evolution, he argued, is not random, but strongly constrained; where environmental niches exist, evolution finds a way to fill them, often with similar creatures.

If Gould is right, a vast number of accidents both large and small determine the forms of living organisms on planet earth.  If this asteroid that veered a bit or that tiny proto-mammal hadn’t made it across a short, shallow stretch of water, then someone other than us would be looking at an altogether different catalog of creatures.  Or no one would be looking at all, because the existence of intelligent lookers is one more sheer accident. 

If Conway Morris is right, run the algorithm back to the dinosaurs and hit play.  You will get a lot of the same organic forms as we have now.  That is because evolutionary pathways are highly constrained.  Eyes and wings are useful relatively easy to produce in the evolutionary history of many branches of life, so we have their independence emergence (called convergence in evolutionary theory) about four times.  Eyes emerged independently about 40 times that we know of.  Here is my favorite example. 

Everywhere Conway Morris looked, he saw convergence. He points, for example, to the appearance of tiger-like animals in both North and South America – animals that arose along separate evolutionary paths (the North American version was a placental mammal, the ancestors of today’s wild cats; in South America, they were marsupials)

What this means is that there was an evolutionary niche, a certain condition (meaning plentiful large and small prey) available for a certain type of predator (a cat to be specific). 

I am not at all sure that these two interpretations of evolution are all that much at odds.  I am sure that they recapitulate one of the original arguments in the history of philosophy.  Aristotle argued that these here animals have the forms that they have because they happened to descend from similar groups of animals.  Aristotle only toyed very briefly with the idea of evolution, but if you add natural selection and evolutionary history to his view, you get something like Gould’s view. 

Plato argued that the forms of actual things exist apart from those things and determine how those things come to be and what they are.  Human beings are intelligent because intelligence as an idea is always waiting to shape humans into being.  If we interpret evolutionary niches as Platonic forms, we get pretty much what Plato was talking about. 

Worrying about knowing everything is a very silly worry and an even sillier way to defend the humanities.  If you want to understand how such actual creatures as Shakespeare and such fictional creatures as Romeo and Juliet come to be, you have to read Shakespeare.  If you do, you will be able to tell evolutionary biologists something they will want to know.  That is the way to defend the humanities. 

Borges, Plato, & Natural Selection

Tomas Luis Borges had an astonishing genius for channeling vast currents in the history of ideas into the narrow stream of a compelling story.  One of his most frequently mentioned stories was “The Library of Babel”.  It begins with these words:

The universe (which others call the Library) is composed of an indefinite and perhaps infinite number of hexagonal galleries, with vast air shafts between, surrounded by very low railings. From any of the hexagons one can see, interminably, the upper and lower floors. The distribution of the galleries is invariable. Twenty shelves, five long shelves per side, cover all the sides except two; their height, which is the distance from floor to ceiling, scarcely exceeds that of a normal bookcase. One of the free sides leads to a narrow hallway which opens onto another gallery, identical to the first and to all the rest. 

If you haven’t read the story, I am about to do you the terrible disservice of spoiling the end.  I can only offer the defense that many more people have read about the story than have actually read the story. 

The library consists of a vast but not infinite set of books. 

There are five shelves for each of the hexagon's walls; each shelf contains thirty-five books of uniform format; each book is of four hundred and ten pages; each page, of forty lines, each line, of some eighty letters which are black in color. There are also letters on the spine of each book; these letters do not indicate or prefigure what the pages will say… Second: The orthographical symbols are twenty-five in number.

The library consists of all the books that are logically possible, given the parameters just listed.  To say that this library would be vast is meaningful only in the strictest mathematical sense.  It would be, to say the least, astronomical in extent.  Consider that in this library somewhere is a perfect copy of Shakespeare’s Richard III.  There is also a copy of Dickey Three with alternative endings, including one in which the villain is rescued by the Mighty Morphin’ Power Rangers.  There are perfectly accurate histories of the life of every single human being and indeed every single organism along with alternative histories.  In one of them I am married to two Victoria’s Secret models. 

Of course, all of the coherent reads will be only a drop in the bucket.  Most of the books will be incoherent jumbles of nonsense.  One of the books will consist of nothing but the word “word” over and over again. 

This brilliant thought problem, in the form of a librarian’s musings on the bizarre world that he inhabits, is another version of the infamous infinite monkey theorem.  Could a set of monkeys (say 100), typing randomly, eventually produce a copy of Richard III?  According to the theorem, which I believe to be logically sound, the answer is “yes, given enough time”.  However, the time required is unimaginably vast.  Even to produce “Now is the winter of our discontent” would require more time, I recently calculated, than the age of the Kosmos itself.  Along the way you would get a vast number of half finished, garbled, and alternative versions. 

Darwin’s great idea was to explain how you could get Shakespeare himself out of processes just as random as our team of monkeys or Borges’ library.  All you need is some device that persistently steers the primates in the right direction.  If the monkeys keep typing now is the winter over and over again until they get the next letter right and then keep typing that…  That is what natural selection does. 

These reflections were set in motion by wonderful essay in Aeon.  Andreas Wagner, professor in the Institute of Evolutionary Biology and Environmental Studies at the University of Zurich and at the Santa Fe Institute in New Mexico, argues that Darwinian evolution could not work without “nature’s library of Platonic forms.” 

How do random DNA changes lead to innovation? Darwin’s concept of natural selection, although crucial to understand evolution, doesn’t help much. The thing is, selection can only spread innovations that already exist. The botanist Hugo de Vries said it best in 1905: ‘Natural selection can explain the survival of the fittest, but it cannot explain the arrival of the fittest.’…

A metaphor might help to clarify the problem. Imagine a giant library of books containing all possible sequences of letters in the alphabet. Such a library would be huge beyond imagination, and most of its texts would of course be pure gibberish. But some would contain islands of intelligibility – a word here, a Haiku there – in a sea of random letters. Still others would tell all stories real and imagined: not only Dickens’s Oliver Twist or Goethe’s Faust, but all possible novels and dramas, the biography of every single human, true and false histories of the world, of other worlds as yet unseen, and so on. Some texts would include descriptions of countless technological innovations, from the wheel to the steam engine to the transistor – including countless innovations yet to be imagined. But the chances of choosing such a valuable tome by chance are minuscule.

That giant library is, of course, Borges’ library, though Wagner doesn’t give credit here.  He does present the same problem. 

A protein is a volume in a library just like this, written in a 20-letter alphabet of amino acids. And while protein texts might not be as long as Tolstoy’s War and Peace, their total number is still astonishing. For example, a library of every possible amino acid string that is 500 letters long would contain more than 10⁶⁰⁰ texts – a one with 600 trailing zeros. That vastly outnumbers the atoms in the visible universe.

The library is a giant space of the possible, encoding all the proteins that could be useful to life. But here’s the thing: evolution can’t simply look up the chemicals it needs in a giant catalogue. No, it has to inch its way painstakingly along the stacks.

So how does natural selection find the next viable protein sequence?  How does this mindless process find the path that arrives at viable minds? 

For more than a decade, this endeavour has been a focus of my research at the University of Zurich and at the Santa Fe Institute in the US. We evolve molecules in the laboratory and record their journey through these libraries, together with any new and useful texts they find. We also map the locations of millions of molecules that nature’s populations have discovered in their billion-year journey. We use powerful computer simulations to explore those parts of a library that nature has not yet discovered. Through these efforts, we and others have found a system of organisation in these libraries that is as strange as it is perfect for guideless exploration.

One of its features is easily explained once we observe that neighbouring texts in nature’s library have similar letter sequences, and the closest texts – immediate neighbours – differ in just a single letter.

If natural selection had to pick at random from the possible protein sequences, no conceivable time would suffice for evolutionary processes.  But it didn’t have to do that.  The basic molecules on which natural selection works (at the molecular level) open up a large but not vast number of pathways.  Many different directions are open, but only so many.  A library of possible forms is on the same shelf and it is a big shelf, but manageable.  Certain pathways prove very fruitful, and natural selection moves up and down them again and again.  Many different combinations of genes work the same outcomes along a viable pathway. 

The remarkable thing is, having so many different ways to say the same thing means that there are many more possible slips of the tongue. And with each slip of the tongue comes the possibility of saying something different. Just as the word GOLD emerges from a single letter change in MOLD, some neighbours of a text express new meanings. And as the browsers work their way through each synonym for some original text, different innovations become accessible. By creating safe paths through the library, genotype networks create the very possibility of innovation.

Let me put this point as strongly as I can. Without these pathways of synonymous texts, these sets of genes that express precisely the same function in ever-shifting sequences of letters, it would not be possible to keep finding new innovations via random mutation. Evolution would not work.

What Wagner thinks, if I read him right, is that the molecular material that natural selection began to work on from the very beginning of life on earth already contained a large but manageable set of forms.  If it hadn’t, evolution could not have been possible.  He recognizes this library of viable forms to be Platonic.  That makes two of us.