A cherry is a cherry is a cherry

Life is Simple: How Occam’s Razor Sets Science Free and Shapes the Universe
by Johnjoe McFadden, reviewed for the Spectator, 28 August 2021

Astonishing, where an idea can lead you. You start with something that, 800 years hence, will sound like it’s being taught at kindergarten: Fathers are fathers, not because they are filled with some “essence of fatherhood”, but because they have children.

Fast forward a few years, and the Pope is trying to have you killed.

Not only have you run roughshod over his beloved eucharist (justified, till then, by some very dodgy Aristotelian logic-chopping); you’re also saying there’s no “essence of kinghood”, neither. If kings are only kings because they have subjects, then, said William of Occam, “power should not be entrusted to anyone without the consent of all”. Heady stuff for 1334.

How this progression of thought birthed the very idea of modern science, is the subject of what may be the most sheerly enjoyable history of science of recent years.

William was born around 1288 in the little town of Ockham in Surrey. He was probably an orphan; at any rate he was given to the Franciscan order around the age of eleven. He shone at Greyfriars in London, and around 1310 was dispatched to Oxford’s newfangled university.

All manner of intellectual, theological and political shenanigans followed, mostly to do with William’s efforts to demolish almost the entire edifice of medieval philosophy.

It needed demolishing, and that’s because it still held to Aristotle’s ideas about what an object is. Aristotle wondered how single objects and multiples can co-exist. His solution: categorise everything. A cherry is a cherry is a cherry, and all cherries have cherryness in common. A cherry is a “universal”; the properties that might distinguish one cherry from another are “accidental”.

The trouble with Aristotle’s universals, though, is that they assume a one-to-one correspondence between word and thing, and posit a universe made up of a terrifying number of unique things — at least one for each noun or verb in the language.

And the problem with that is that it’s an engine for making mistakes.

Medieval philosophy relied largely on syllogistic reasoning, juggling things into logical-looking relations. “Socrates is a man, all men are mortal, so Socrates is mortal.”

So he is, but — and this is crucial — this conclusion is arrived at more by luck than good judgement. The statement isn’t “true” in any sense; it’s merely internally consistent.

Imagine we make a mistake. Imagine we spring from a society where beards are pretty much de rigeur (classical Athens, say, or Farringdon Road). Imagine we said, “Socrates is a man, all men have beards, therefore Socrates has a beard”?

Though one of its premises is wrong, the statement barrels ahead regardless; it’s internally consistent, and so, if you’re not paying attention, it creates the appearance of truth.

But there’s worse: the argument that gives Socates a beard might actually be true. Some men do have beards. Socrates may be one of them. And if he is, that beard seems — again, if you’re not paying attention — to confirm a false assertion.

William of Occam understood that our relationship with the world is a lot looser, cloudier, and more indeterminate than syllogistic logic allows. That’s why, when a tavern owner hangs a barrel hoop outside his house, passing travellers know they can stop there for a drink. The moment words are decoupled from things, then they act as signs, negotiating flexibly with a world of blooming, buzzing confusion.

Once we take this idea to heart, then very quickly — and as a matter of taste more than anything — we discover how much more powerful straightforward explanations are than complicated ones. Occam came up with a number of versions of what even then was not an entirely new idea: “It is futile to do with more what can be done with less,” he once remarked. Subsequent formulations do little but gild this lily.

His idea proved so powerful, three centuries later the French theologian Libert Froidmont coined the term “Occam’s razor”, to describe how we arrive at good explanations by shaving away excess complexity. As McFadden shows, that razor’s still doing useful work.

Life is Simple is primarily a history of science, tracing William’s dangerous idea through astronomy, cosmology, physics and biology, from Copernicus to Brahe, Kepler to Newton, Darwin to Mendel, Einstein to Noether to Weyl. But McFadden never loses sight of William’s staggering, in some ways deplorable influence over the human psyche as a whole. For if words are independent of things, how do we know what’s true?

Thanks to William of Occam, we don’t. The universe, after Occam, is unknowable. Yes, we can come up with explanations of things, and test them against observation and experience; but from here on in, our only test of truth will be utility. Ptolemy’s 2nd-century Almagest, a truly florid description of the motions of the stars and planetary paths, is not and never will be *wrong*; the worst we can say is that it’s overcomplicated.

In the Coen brothers’ movie The Big Lebowski, an exasperated Dude turns on his friend: “You’re not *wrong*, Walter” he cries, “you’re just an asshole.” William of Occam is our universal Walter, and the first prophet of our disenchantment. He’s the friend we wish we’d never listened to, when he told us Father Christmas was not real.

The Art of Conjecturing

Reading Katy Börner’s Atlas of Forecasts: Modeling and mapping desirable futures for New Scientist, 18 August 2021

My leafy, fairly affluent corner of south London has a traffic congestion problem, and to solve it, there’s a plan to close certain roads. You can imagine the furore: the trunk of every kerbside tree sports a protest sign. How can shutting off roads improve traffic flows?

The German mathematician Dietrich Braess answered this one back in 1968, with a graph that kept track of travel times and densities for each road link, and distinguished between flows that are optimal for all cars, and flows optimised for each individual car.

On a Paradox of Traffic Planning is a fine example of how a mathematical model predicts and resolves a real-world problem.

This and over 1,300 other models, maps and forecasts feature in the references to Katy Börner’s latest atlas, which is the third to be derived from Indiana University’s traveling exhibit Places & Spaces: Mapping Science.

Atlas of Science: Visualizing What We Know (2010) revealed the power of maps in science; Atlas of Knowledge: Anyone Can Map (2015), focused on visualisation. In her third and final foray, Börner is out to show how models, maps and forecasts inform decision-making in education, science, technology, and policymaking. It’s a well-structured, heavyweight argument, supported by descriptions of over 300 model applications.

Some entries, like Bernard H. Porter’s Map of Physics of 1939, earn their place thanks purely to their beauty and for the insights they offer. Mostly, though, Börner chooses models that were applied in practice and made a positive difference.

Her historical range is impressive. We begin at equations (did you know Newton’s law of universal gravitation has been applied to human migration patterns and international trade?) and move through the centuries, tipping a wink to Jacob Bernoulli’s “The Art of Conjecturing” of 1713 (which introduced probability theory) and James Clerk Maxwell’s 1868 paper “On Governors” (an early gesture at cybernetics) until we arrive at our current era of massive computation and ever-more complex model building.

It’s here that interesting questions start to surface. To forecast the behaviour of complex systems, especially those which contain a human component, many current researchers reach for something called “agent-based modeling” (ABM) in which discrete autonomous agents interact with each other and with their common (digitally modelled) environment.

Heady stuff, no doubt. But, says Börner, “ABMs in general have very few analytical tools by which they can be studied, and often no backward sensitivity analysis can be performed because of the large number of parameters and dynamical rules involved.”

In other words, an ABM model offers the researcher an exquisitely detailed forecast, but no clear way of knowing why the model has drawn the conclusions it has — a risky state of affairs, given that all its data is ultimately provided by eccentric, foible-ridden human beings.

Börner’s sumptuous, detailed book tackles issues of error and bias head-on, but she left me tugging at a still bigger problem, represented by those irate protest signs smothering my neighbourhood.

If, over 50 years since the maths was published, reasonably wealthy, mostly well-educated people in comfortable surroundings have remained ignorant of how traffic flows work, what are the chances that the rest of us, industrious and preoccupied as we are, will ever really understand, or trust, all the many other models which increasingly dictate our civic life?

Borner argues that modelling data can counteract misinformation, tribalism, authoritarianism, demonization, and magical thinking.

I can’t for the life of me see how. Albert Einstein said, “Everything should be made as simple as possible, but no simpler.” What happens when a model reaches such complexity, only an expert can really understand it, or when even the expert can’t be entirely sure why the forecast is saying what it’s saying?

We have enough difficulty understanding climate forecasts, let alone explaining them. To apply these technologies to the civic realm begs a host of problems that are nothing to do with the technology, and everything to do with whether anyone will be listening.

The old heave-ho

The Story of Work: A New History of Humankind by Jan Lucassen, reviewed for the Telegraph 14 August 2021

“How,” asks Dutch social historian Jan Lucassen, “could people accept that the work of one person was rewarded less than that of another, that one might even be able to force the other to do certain work?”

The Story of Work is just that: a history of work (paid or otherwise, ritual or for a wage, in the home or out of it) from peasant farming in the first agrarian societies to gig-work in the post-Covid ruins of the high street, and spanning the historical experiences of working people on all five inhabited continents. The writing is, on the whole, much better than the sentence you just read, but no less exhausting. At worst, it put me in mind of the work of English social historian David Kynaston; super-precise prose stitched together to create an unreadably compacted narrative.

For all its abstractions, contractions and signposting, however, The Story of Work is full of colour, surprise and human warmth. What other social history do you know writes off the Industrial Revolution as a net loss to music? “Just think of the noise from rattling machines that made it impossible to talk,” Lucassen writes, “in contrast to small workplaces or among larger troupes of workers who mollified work in the open air by singing shanties and other work songs.”

For 98 per cent of our species’ history we lived lives of reciprocal altruism in hunting-and-gathering clan groups. With the advent of farming and the formation of the first towns came surpluses and, for the first time, the feasibility of distributing resources unequally.

At first, conspicuous generosity ameliorated the unfairnesses. As the sixteenth-century French judge Étienne de la Boétie wrote: “theatres, games, plays, spectacles, marvellous beasts, medals, tableaux, and other such drugs were for the people of antiquity the allurements of serfdom, the price of their freedom, the tools of tyranny.” (The Story of Work is full of riches of this sort: strip off the narrative, and there’s a cracking miscellany still to enjoy.)

Lucassen diverges from the popular narrative (in which the invention of agriculture is the fount of all our ills) on several points. First, agricultural societies do not inevitably become marketplaces. Bantu-speaking agriculturalists spread across central, eastern and southern Africa between 3500 BCE and 500 CE, while maintaining perfect equality. “Agriculture and egalitarianism are compatible,“ says Lucassen.

It’s not the crops, but the livestock, that are to blame for our expulsion from hunter-gatherer Eden. If notions of private property had to arise anywhere, they surely arose, Lucassen argues, among those innocent-looking shepherds and shepherdesses, whose waterholes may have been held in common but whose livestock most certainly were not. Animals were owned by individuals or households, whose success depended on them knowing every single individual in their herd.

Having dispatched the idea that agriculture made markets, Lucassen then demolishes the idea that markets made inequality. Inequality came first. It does not take much specialism to arise within a group before some acquire more resources than others. Managing this inequality doesn’t need anything so complex as a market. All it needs is an agreement. Lucassen turns to India, and the social ideologies that gave rise, from about 600 BC, to the Upanishads and the later commentaries on the Vedas: the evolving caste system, he says, is a textbook example of how human suffering can be explained to an entire culture’s satisfaction ”without victims or perpetrators being able to or needing to change anything about the situation”.

Markets, by this light, become a way of subverting the iniquitous rhetorics cooked up by rulers and their priests. Why, then, have markets not ushered in a post-political Utopia? The problem is not to do with power. It’s to do with knowledge. Jobs used to be *hard*. They used to be intellectually demanding. Never mind the seven-year apprenticeships of Medieval Europe, what about the jobs a few are still alive to remember? Everything, from chipping slate out of a Welsh quarry to unloading a cargo boat while maintaining its trim, took what seem now to be unfeasible amounts of concentration, experience and skill.

Now, though — and even as they are getting fed rather more, and rather more fairly, than at any other time in world history — the global proletariat are being starved, by automation, of the meaning of their labour. The bloodlessness of this future is not a subject Lucassen spends a great many words on, but it informs his central and abiding worry, which is that slavery — a depressing constant in his deep history of labour — remains a constant threat and a strong future possibility. The logics of a slave economy run frighteningly close to the skin in many cultures: witness the wrinkle in the 13th Amendment of the US constitution that legalises the indentured servitude of (largely black) convicts, or the profits generated for the global garment industry by interned Uighurs in China. Automation, and its ugly sister machine surveillance, seem only to encourage such experiments in carceral capitalism.

But if workers of the world are to unite, around what banner should they gather? Lucassen identifies only two forms of social agreement that have ever reconciled us to the unfair distribution of reward. One is redistributive theocracy. “Think of classical Egypt and the pre-Columbian civilizations,” he writes, “but also of an ‘ideal state’ like the Soviet Union.”

The other is the welfare state. But while theocracies have been sustained for centuries or even millennia, the welfare state, thus far, has a shelf life of only a few decades, and is easily threatened.

Exhausted yet enlightened, any reader reaching the end of Lucassen’s marathon will understand that the problem of work runs far deeper than politics, and that the grail of a fair society will only come nearer if we pay attention to real experiences, and resist the lure of utopias.

“It’s wonderful what a kid can do with an Erector Set”

Reading Across the Airless Wilds by Earl Swift for the Times, 7 August 2021

There’s something about the moon that encourages, not just romance, not just fancy, but also a certain silliness. It was there in spades at the conference organised by the American Rocket Society in Manhattan in 1961. Time Magazine delighted in this “astonishing exhibition of the phony and the competent, the trivial and the magnificent.” (“It’s wonderful what a kid can do with an Erector Set”, one visiting engineer remarked.)

But the designs on show thefre were hardly any more bizarre than those put forward by the great minds of the era. The German rocket pioneer Hermann Oberth wrote an entire book advocating a moon car that could, if necessary, pogo-stick about the satellite. When Howard Seifert, the American Rocket Society’s president, advocated abandoning the car and preserving the pogo stick — well, Siefert’s “platform” might not have made it to the top of NASA’s favoured designs for a moon vehicle, but it was taken seriously.

Earl Swift is not above a bit of fun and wonder, but the main job of Across the Airless Wilds (a forbiddingly po-faced title for such an enjoyable book) is to explain how the oddness of the place — barren, airless, and boasting just one-sixth Earth’s gravity — tended to favour some very odd design solutions. True, NASA’s lunar rover, which actually flew on the last three Apollo missions, looks relatively normal, like a car (or at any rate, a go-kart). But this was really to do with weight constraints, budgets and historical accidents; a future in which the moon is explored by pogo-stick is still not quite out of the running.

For all its many rabbit-holes, this is a clear and compelling story about three men: Sam Romano, boss of General Motors’s lunar program, his visionary off-road specialist Mieczyslaw Gregory Bekker (Greg to his American friends) and Greg’s invaluable engineer Ferenc (Frank) Pavlics. These three were toying with the possibility of moon vehicles a full two years before the US boasted any astronauts, and the problems they confronted were not trivial. Until Bekker came along, tyres, wheels and tracks for different surfaces were developed more or less through informed trial and error. It was Bekker who treated off-roading as an intellectual puzzle as rigorous as the effort to establish the relationship between a ship’s hull and water, or a plane’s wing and the air it rides.

Not that rigour could gain much toe-hold in the early days of lunar design, since no-one could be sure what the consistency of the moon’s surface actually was. It was probably no dustier than an Earthbound desert, but there was always the nagging possibility that a spacecraft and its crew, landing on a convenient lunar plain, might vanish into some ghastly talcum quicksand.

On 3 February 1966 the Soviet probe Luna 9 put paid to that idea, settling, firmly and without incident, onto the Ocean of Storms. Though their plans for a manned mission had been abandoned, the Soviets were no bit player. Four years later it was an eight-wheel Soviet robot, Lunokhod-17, that first drove across the moon’s surface. Seven feet long and four feet tall, it upstaged NASA’s rovers nicely, with its months and miles of journey time, 25 soil samples and literally thousands of photographs.

Meanwhile NASA was having to re-imagine its Lunar Roving Vehicle any number of times, as it sought to wring every possible ounce of value from a programme that was being slashed by Congress a good year before Neil Armstrong even set foot on the Moon.

Conceived when it was assumed Apollo would be the first chapter in a long campaign of exploration and settlement, the LRV was being shrunk and squeezed and simplified to fit through an ever-tightening window of opportunity. This is the historical meat of Swift’s book, and he handles the technical, institutional and commercial complexities of the effort with a dramatist’s eye.

Apollo was supposed to pave the way for two-rocket missions. When they vanished from the schedule, the rover’s future hung in doubt. Without a second Saturn to carry cargo, any rover bound for the moon would have to be carried on the same lunar module that carried the crew. No-one knew if this was even possible.

There was, however, one wedge-shaped cavity still free between the descent stage’s legs: an awkward triangle “about the size and shape of a pup tent standing on its end.” So it was that the LRV, tht once boasted six wheels and a pressurised cabin, ended up the machine a Brompton folding bike wants to be when it grows up.

Ironically, it was NASA’s dwindling prospects post-Apollo that convinced its managers to origami something into that tiny space, just a shade over seventeen months prior to launch. Why not wring as much value out of Apollo’s last missions as possible?

The result was a triumph, though it maybe didn’t look like one. Its seats were basically deckchairs. It had neither roof, nor body. There was no steering wheel, just a T-bar the astronaut lent on. It weighed no more than one fully kitted-out astronaut, and its electric motors ground out just one horsepower. On the flat, it reached barely ten miles an hour.

But it was superbly designed for the moon, where a turn at 6MPH had it fishtailing like a speedboat, even as it bore more than twice its weight around an area the size of Manhattan.

In a market already oversaturated with books celebrating the 50th anniversary of Apollo in 2019 (many of them very good indeed) Swift finds his niche. He’s not narrow: there’s plenty of familiar context here, including a powerful sketch of the former Nazi rocket scientist Wernher von Braun. He’s not especially folksy, or willfully eccentric: the lunar rover was a key element in the Apollo program, and he wants it taken seriously. Swift finds his place by much more ingenious means — by up-ending the Apollo narrative entirely (he would say he was turning it right-side up) so that every earlier American venture into space was preparation for the last three trips to the moon.

He sets out his stall early, drawing a striking contrast between the travails of Apollo 14 astronauts Alan Shepard Jr and Edgar Mitchell — slugging half a mile up the the wall of the wrong crater, dragging a cart — with the vehicular hijinks of Apollo 15’s Dave Scott and Jim Irwin, crossing a mile of hummocky, cratered terrain rimmed on two sides by mountains the size of Everest, to a spectacular gorge, then following its edge to the foot of a huge mountain, then driving up its side.

Detailed, thrilling accounts of the two subsequent Rover-equipped Apollo missions, Apollo 16 in the Descartes highlands and Apollo 17 in the Taurus-Littrow Valley, carry the pointed message that the viewing public began to tune out of Apollo just as the science, the tech, and the adventure had gotten started.

Swift conveys the baffling, unreadable lunar landscape very well, but Across the Airless Wilds is above all a human story, and a triumphant one at that, about NASA’s most-loved machine. “Everybody you meet will tell you he worked on the rover,” remarks Eugene Cowart, Boeing’s chief engineer on the project. “You can’t find anybody who didn’t work on this thing.”

Sod provenance

Is the digital revolution that Pixar began with Toy Story stifling art – or saving it? An article for the Telegraph, 24 July 2021

In 2011 the Westfield shopping mall in Stratford, East London, acquired a new public artwork: a digital waterfall by the Shoreditch-based Jason Bruges Studio. The liquid-crystal facets of the 12 metre high sculpture form a subtle semi-random flickering display, as though water were pouring down its sides. Depending on the shopper’s mood, this either slakes their visual appetite, or leaves them gasping for a glimpse of real rocks, real water, real life.

Over its ten-year life, Bruges’s piece has gone from being a comment about natural processes (so soothing, so various, so predictable!) to being a comment about digital images, a nagging reminder that underneath the apparent smoothness of our media lurks the jagged line and the stair-stepped edge, the grid, the square: the pixel, in other words.

We suspect that the digital world is grainier than the real, coarser, more constricted, and stubbornly rectilinear. But this is a prejudice, and one that’s neatly punctured by a new book by electrical engineer and Pixar co-founder Alvy Ray Smith, “A Biography of the Pixel”. This eccentric work traces the intellectual genealogy of Toy Story (Pixar’s first feature-length computer animation in 1995) over bump-maps and around occlusions, along traced rays and through endless samples, computations and transformations, back to the mathematics of the eighteenth century.

Smith’s whig history is a little hard to take — as though, say, Joseph Fourier’s efforts in 1822 to visualise how heat passed through solids were merely a way-station on the way to Buzz Lightyear’s calamitous launch from the banister rail — but it’s a superb short-hand in which to explain the science.

We can use Fourier’s mathematics to record an image as a series of waves. (Visual patterns, patterns of light and shade and movement, “can be represented by the voltage patterns in a machine,” Smith explains.) And we can recreate these waves, and the image they represent, with perfect fidelity, so long as we have a record of the points at the crests and troughs of each wave.

The locations of these high- and low-points, recorded as numerical coordinates, are pixels. (The little dots you see if you stare far too closely at your computer screen are not pixels; strictly speaking, they’re “display elements”.)

Digital media do not cut up the world into little squares. (Only crappy screens do that). They don’t paint by numbers. On the contrary, they faithfully mimic patterns in the real world.

This leads Smith to his wonderfully upside-down-sounding catch-line: “Reality,” he says, ”is just a convenient measure of complexity.”

Once pixels are converted to images on a screen, they can be used to create any world, rooted in any geometry, and obeying any physics. And yet these possibilities remain largely unexplored. Almost every computer animation is shot through a fictitious “camera lens”, faithfully recording a Euclidean landscape. Why are digital animations so conservative?

I think this is the wrong question: its assumptions are faulty. I think the ability to ape reality at such high fidelity creates compelling and radical possibilities of its own.

I discussed some of these possibilities with Paul Franklin, co-founder of the SFX company DNEG, and who won Oscars for his work on Christopher Nolan’s sci-fi blockbusters Interstellar (2014) and Inception (2010). Franklin says the digital technologies appearing on film sets in the past decade — from lighter cameras and cooler lights to 3-D printed props and LED front-projection screens — are positively disrupting the way films are made. They are making film sets creative spaces once again, and giving the director and camera crew more opportunities for on-the-fly creative decision making. “We used a front-projection screen on the film Interstellar, so the actors could see what visual effects they were supposed to be responding to,” he remembers. “The actors loved being able to see the super-massive black hole they were supposed to be hurtling towards. Then we realised that we could capture an image of the rotating black hole’s disc reflecting in Matthew McConaughey’s helmet: now that’s not the sort of shot you plan.”

Now those projection screens are interactive. Franklin explains: “Say I’m looking down a big corridor. As I move the camera across the screen, instead of it flattening off and giving away the fact that it’s actually just a scenic backing, the corridor moves with the correct perspective, creating the illusion of a huge volume of space beyond the screen itself.“

Effects can be added to a shot in real-time, and in full view of cast and crew. More to the point, what the director sees through their viewfinder is what the audience gets. This encourages the sort of disciplined and creative filmmaking Melies and Chaplin would recognise, and spells an end to the deplorable industry habit of kicking important creative decisions into the long grass of post-production.

What’s taking shape here isn’t a “good enough for TV” reality. This is a “good enough to reveal truths” reality. (Gargantua, the spinning black hole at Interstellar’s climax, was calculated and rendered so meticulously, it ended up in a paper for the journal Classical and Quantum Gravity.) In some settings, digital facsimile is becoming, literally, a replacement reality.

In 2012 the EU High Representative Baroness Ashton gave a physical facsimile of the burial chamber of Tutankhamun to the people of Egypt. The digital studio responsible for its creation, Factum Foundation, has been working in the Valley of the Kings since 2001, creating ever-more faithful copies of places that were never meant to be visited. They also print paintings (by Velasquez, by Murillo, by Raphael…) that are indistinguishable from the originals.

From the perspective of this burgeoning replacement reality, much that is currently considered radical in the art world appears no more than a frantic shoring-up of old ideas and exhausted values. A couple of days ago Damien Hirst launched The Currency, a physical set of dot paintings the digitally tokenised images of which can be purchased, traded, and exchanged for the real paintings.

Eventually the purchaser has to choose whether to retain the token, or trade it in for the physical picture. They can’t own both. This, says Hirst, is supposed to challenge the concept of value through money and art. Every participant is confronted with their perception of value, and how it influences their decision.

But hang on: doesn’t money already do this? Isn’t this what money actually is?

It can be no accident that non-fungible tokens (NFTs), which make bits of the internet ownable, have emerged even as the same digital technologies are actually erasing the value of provenance in the real world. There is nothing sillier, or more dated looking, than the Neues Museum’s scan of its iconic bust of Nefertiti, released free to the public after a complex three-year legal battle. It comes complete with a copyright license in the bottom of the bust itself — a copyright claim to the scan of a 3,000-year-old sculpture created 3,000 miles away.

Digital technologies will not destroy art, but they will erode and ultimately extinguish the value of an artwork’s physical provenance. Once facsimiles become indistinguishable from originals, then originals will be considered mere “first editions”.

Of course literature has thrived for many centuries in such an environment; why should the same environment damage art? That would happen only if art had somehow already been reduced to a mere vehicle for financial speculation. As if!

 

Eagle-eyed eagles and blind, breathless fish

Secret Worlds: The extraordinary senses of animals by Martin Stevens, reviewed for New Scientist, 21 July 2021

Echo-locating bats use ultrasound to map their lightless surroundings. The information they gather is fine-grained — they can tell the difference between the wing cases and bodies of a beetle, and the scales of a moth’s wings. The extremely high frequency of ultrasound — far beyond our own ability to hear — generates clearer, less “blurry” sonic images. And we should be jolly glad bats use it, and these creatures are seriously noisy. A single bat, out for lunch, screams at around 140 decibels. Someone shouting a metre away generates only 90.

Since 2013, when his textbook Sensory Ecology, Behaviour, and Evolution was published, Martin Stevens, a professor at Exeter University in the UK, has had it in mind to write a popular version — a book that, while paying its dues to the extraordinary sensory abilities of animals, also has something to say about the evolution and plasticity of the senses, and above all the cost of acquiring them.

“Rather than seeing countless species all around us, each with every single one of their sense being a pinnacle of what is possible,” he writes, “we instead observe that evolution and development has honed those senses that the animal needs most, and scaled back on the others.” For every eagle-eyed, erm, eagle, there is a blind fish.

Stevens presents startling data about the expense involved in sensing the world. A full tenth of the energy used by a blowfly (Calliphora vicina) at rest is used up maintaining its photoreceptors and associated nerve cells.

Stevens also highlights some remarkable cost-saving strategies. The ogre-faced spider from Australia (Deinopsis subrufa) has such large, sensitive and expensive-to-maintain eyes, it breaks down photoreceptors and membranes during the day, and regenerates them at night in order to hunt.

Senses are too expensive to stick around when they’re not needed; so they disappear and reappear over evolutionary time. Their genetic mechanisms are surprisingly parsimonious. The same genetic pathways crop up again and again, in quite unrelated species. The same, or similar mutations have occurred in the Prestin gene in both dolphins bats, unrelated species that both echolocate: “not surprising,” Stevens observes, “if evolution has limited genetic material to act on in the first place”.

Stevens boils his encyclopedic knowledge down to three animals per chapter, and each chapter focuses on a different sense. This rather mechanistic approach serves him surprisingly well; this is a field full of stories startling enough not to need much window-dressing. While Stevens’s main point is nature’s parsimony, it’s those wonderful extremes that will stick longest in the mind of the casual reader.

There are many examples of familiar senses brought to a rare peak. For example, the whiskers of a harbour seal (Phoca vitulina) help it find a buried flatfish by nothing more than the water flow created by the fish’s breathing.

More arresting still are the chapters devoted to senses wholly unfamiliar to us. Using their infra-red thermal receptors, vampire bats pick out particular blood vessels to bite into. Huge numbers of marine species detect minute amounts of electricity, allowing them to hunt, elude predators, and even to attract mates.

As for the magnetic sense, Stevens reckons “it is no exaggeration to say that understanding how [it] works has been one of the great mysteries in biology.”

There are two major competing theories to explain the magnetic senses, one relating to the presence of crystals in the body that react to magnetic fields, the other to light-dependent chemical processes occurring in the eyes in response to magnetic information. Trust the robin to complicate the picture still further; it seems to boast both systems, one for use in daylight and one for use in the dark!

And what of those satellite images of cows and deer that show herds lining themselves up along lines of magnetic force, their heads invariably pointing to magnetic north?

Some science writers are, if anything, over-keen to entertain. Stevens, by contrast, is the real deal: the unassuming keeper of a cabinet of true wonders.

How many holes has a straw?

Reading Jordan Ellenberg’s Shape for the Telegraph, 7 July 2021

“One can’t help feeling that, in those opening years of the 1900s, something was in the air,” writes mathematician Jordan Ellenburg.

It’s page 90, and he’s launching into the second act of his dramatic, complex history of geometry (think “History of the World in 100 Shapes”, some of them very screwy indeed).
For page after reassuring page, we’ve been introduced to symmetry, to topology, and to the kinds of notation that make sense of knotty-sounding questions like “how many holes has a straw”?

Now, though, the gloves are off, as Ellenburg records the fin de siecle’s “painful recognition of some unavoidable bubbling randomness at the very bottom of things.”
Normally when sentiments of this sort are trotted out, they’re there to introduce readers to the wild world of quantum mechanics (and, incidentally, we can expect a lot of that sort of thing in the next few years: there’s a centenary looming). Quantum’s got such a grip on our imagination, we tend to forget that it was the johnny-come-lately icing on an already fairly indigestible cake.

A good twenty years before physical reality was shown to be unreliable at small scales, mathematicians were pretzeling our very ideas of space. They had no choice: at the Louisiana Purchase Exposition in 1904, Henri Poincarre, by then the world’s most famous geometer, described how he was trying to keep reality stuck together in light of Maxwell’s famous equations of electromagnetism (Maxwell’s work absolutely refused to play nicely with space). In that talk, he came startlingly close to gazumping Einstein to a theory of relativity.
Also at the same exposition was Sir Ronald Ross, who had discovered that malaria was carried by the bite of the anopheles mosquito. He baffled and disappointed many with his presentation of an entirely mathematical model of disease transmission — the one we use today to predict, well, just about everything, from pandemics to political elections.
It’s hard to imagine two mathematical talks less alike than those of Poincarre and Ross. And yet they had something vital in common: both shook their audiences out of mere three-dimensional thinking.

And thank goodness for it: Ellenburg takes time to explain just how restrictive Euclidean thinking is. For Euclid, the first geometer, living in the 4th century BC, everything was geometry. When he multiplied two numbers, he thought of the result as the area of a rectangle. When he multiplied three numbers, he called the result a “solid’. Euclid’s geometric imagination gave us number theory; but tying mathematical values to physical experience locked him out of more or less everything else. Multiplying four numbers? Now how are you supposed to imagine that in three-dimensional space?

For the longest time, geometry seemed exhausted: a mental gym; sometimes a branch of rhetoric. (There’s a reason Lincoln’s Gettysburg Address characterises the United States as “dedicated to the proposition that all men are created equal”. A proposition is a Euclidean term, meaning a fact that follows logically from self-evident axioms.)

The more dimensions you add, however, the more capable and surprising geometry becomes. And this, thanks to runaway advances in our calculating ability, is why geometry has become our go-to manner of explanation for, well, everything. For games, for example: and extrapolating from games, for the sorts of algorithmical processes we saddle with that profoundly unhelpful label “artificial intelligence” (“artificial alternatives to intelligence” would be better).

All game-playing machines (from the chess player on my phone to DeepMind’s AlphaGo) share the same ghost, the “Markov chain”, formulated by Andrei Markov to map the probabilistic landscape generated by sequences of likely choices. An atheist before the Russian revolution, and treated with predictable shoddiness after it, Markov used his eponymous chain, rhetorically, to strangle religiose notions of free will in their cradle.

From isosceles triangles to free will is quite a leap, and by now you will surely have gathered that Shape is anything but a straight story. That’s the thing about mathematics: it does not advance; it proliferates. It’s the intellectual equivalent of Stephen Leacock’s Lord Ronald, who “flung himself upon his horse and rode madly off in all directions”.

Containing multitudes as he must, Ellenberg’s eyes grow wider and wider, his prose more and more energetic, as he moves from what geometry means to what geometry does in the modern world.

I mean no complaint (quite the contrary, actually) when I say that, by about two-thirds the way in, Ellenberg comes to resemble his friend John Horton Conway. Of this game-playing, toy-building celebrity of the maths world, who died from COVID last year, Ellenburg writes, “He wasn’t being wilfully difficult; it was just the way his mind worked, more associative than deductive. You asked him something and he told you what your question reminded him of.”
This is why Ellenberg took the trouble to draw out a mind map at the start of his book. This and the index offer the interested reader (and who could possibly be left indifferent?) a whole new way (“more associative than deductive”) of re-reading the book. And believe me, you will want to. Writing with passion for a nonmathematical audience, Ellenberg is a popular educator at the top of his game.

Heading north

Reading Forecast by Joe Shute for the Telegraph, 28 June 2021

As a child, journalist Joe Shute came upon four Ladybird nature books from the early 1960s called What to Look For. They described “a world in perfect balance: weather, wildlife and people all living harmoniously as the seasons progress.”

Today, he writes, “the crisply defined seasons of my Ladybird series, neatly quartered like an apple, are these days a mush.”

Forecast is a book about phenology: the study of lifecycles, and how they are affected by season, location and other factors. Unlike behemothic “climate science”, phenology doesn’t issue big data sets or barnstorming visualisations. Its subject cannot be so easily metricised. How life responds to changes in the seasons, and changes in those changes, and changes in the rates of those changes, is a multidimensional study whose richness would be entirely lost if abstracted. Instead, phenology depends on countless parochial diaries describing changes on small patches of land.

Shute, who for more than a decade has used his own diary to fuel the “Weather Watch” column in the Daily Telegraph, can look back and see “where the weather is doing strange things and nature veering spectacularly off course.” Watching his garden coming prematurely to life in late winter, Shute is left “with a slightly sickly sensation… I started to sense not a seasonal cycle, but a spiral.” (130)

Take Shute’s diary together with countless others and tabulate the findings, and you will find that all life has started shifting northwards — insects at a rate of five metres a day, some dragonflies at between 17 and 28 metres a day.

How to write about this great migration? Immediately following several affecting and quite horrifying eye-witness scenes from the global refugee crisis, Shute writes: “The same climate crisis that is rendering swathes of the earth increasingly inhospitable and driving so many young people to their deaths, is causing a similar decline in migratory bird populations.”

I’m being unkind to make a point (in context the passage isn’t nearly so wince-making), but Shute’s not the first to discover it’s impossible to speak across all scales of the climate crisis at once.

Amitav Ghosh’s 2016 The Great Derangement is canonical here. Ghosh explained in painful detail why the traditional novel can’t handle global warming. Here, Shute seems to be proving the same point for non-fiction — or at least, for non-fiction of the meditative sort.

Why doesn’t Shute reach for abstractions? Why doesn’t he reach for climate science, and for the latest IPCC report? Why doesn’t he bloviate?

No, Shute’s made of sterner stuff: he would rather go down with his corracle, stitching together a planet on fire (11 wildfires raging in the Arctic circle in July 2018), human catastrophe, bird armageddon, his and his partner’s fertility problems, and the snore of a sleeping dormouse, across just 250 pages.

And the result? Forecast is a triumph of the most unnerving sort. By the end it’s clearly not Shute’s book that’s coming unstuck: it’s us. Shute begins his book asking “what happens to centuries of folklore, identity and memory when the very thing they subsist on is changing, perhaps for good”, and the answer he arrives at is horrific: folklore, identity and memory just vanish. There is no reverse gear to this thing.

I was delighted (if that is quite the word) to see Shute nailing the creeping unease I’ve felt every morning since 2014. That was the year the Met Office decided to give storms code-names. The reduction of our once rich, allusive weather vocabulary to “weather bombs” and “thunder snow”, as though weather events were best captured in “the sort of martial language usually preserved for the defence of the realm” is Shute’s most telling measure of how much, in this emergency, we have lost of ourselves.

Tally-ho!

Reading Sentient by Jackie Higgins for the Times, 19 June 2021

In May 1971 a young man from Portsmouth, Ian Waterman, lost all sense of his body. He wasn’t just numb. A person has a sense of the position of their body in space. In Waterman, that sense fell away, mysteriously and permanently.

Waterman, now in his seventies, has learned to operate his body rather as the rest of us operate a car. He has executive control over his movements, but no very intimate sense of what his flesh is up to.

What must this be like?

In a late chapter of her epic account of how the senses make sense, and exhibiting the kind of left-field thinking that makes for great TV documentaries, writer-director-producer Jackie Higgins goes looking for answers among the octopuses.

The octopus’s brain, you see, has no fine control over its arms. They pretty much do their own thing. They do, though, respond to the occasional high-level executive order. “Tally-ho!” cries the brain, and the arms gallop off, the brain in no more (or less) control of its transport system than a girl on a pony at a gymkhana.

Is being Ian Waterman anything like being an octopus? Attempts to imagine our way into other animals’ experiences — or other people’s experience, for that matter — have for a long time fallen under the shadow of an essay written in 1974 by American philosopher Thomas Nagel.

“What Is It Like to Be a Bat?” wasn’t about bats so much as to do with consciousness (continuity of). I can, with enough tequila inside me) imagine what it would be like for me to be a bat. But that’s not the same as knowing what’s it’s like for a bat to be a bat.

Nagel’s lesson in gloomy solipsism is all very well in philosophy. Applied to natural history, though — where even a vague notion of what a bat feels like might help a naturalist towards a moment of insight — it merely sticks the perfect in the way of the good. Every sparky natural history writer cocks a snook at poor Nagel whenever the opportunity arises.

Advances in media technology over the last twenty years (including, for birds, tiny monitor-stuffed backpacks) have deluged us in fine-grained information about how animals behave. We now have a much better idea of what (and how) they feel.

Now, you can take this sort of thing only so far. The mantis shrimp (not a shrimp; a scampi) has up to sixteen kinds of narrow-band photoreceptor, each tuned to a different wavelength of light! Humans only have three. Does this mean that the mantis shrimp enjoys better colour vision than we do?

Nope. The mantis shrimp is blind to colour, in the human sense of the word, perceiving only wavelengths. The human brain meanwhile, by processing the relative intensities of those three wavelengths of colour vision, distinguishes between millions of colours. (Some women have four colour receptors, which is why you should never argue with a woman about which curtains match the sofa.)

What about the star-nosed mole, whose octopus-like head is a mass of feelers? (Relax: it’s otherwise quite cute, and only about 2cm long.) Its weird nose is sensitive: it gathers the same amount of information about what it touches, as a regular rodent’s eye gathers about what it sees. This makes the star-nosed mole the fastest hunter we know of, identifying and capturing prey (worms) in literally less than an eyeblink.

What can such a creature tell us about our own senses? A fair bit, actually. That nose is so sensitive, the mole’s visual cortex is used the process the information. It literally sees through its nose.

But that turns out not to be so very strange: Braille readers, for example, really do read through their fingertips, harnessing their visual cortex to the task. One veteran researcher, Paul Bach-y-Rita, has been building prosthetic eyes since the 1970s, using glorified pin-art machines to (literally) impress the visual world upon his volunteers’ backs, chests, even their tongues.

From touch to sound: in the course of learning about bats, I learned here that blind people have been using echolocation for years, especially when it rains (more auditory information, you see); researchers are only now getting a measure of their abilities.

How many senses are there that we might not have noticed? Over thirty, it seems, all served by dedicated receptors, and many of them elude our consciousness entirely. (We may even share the magnetic sense enjoyed by migrating birds! But don’t get too excited. Most mammals seem to have this sense. Your pet dog almost always pees with its head facing magnetic north.)

This embarrassment of riches leaves Higgins having to decide what to include and what to leave out. There’s a cracking chapter here on how animals sense time, and some exciting details about a sense of touch common to social mammals: one that responds specifically to cuddling.

On the other hand there’s very little about our extremely rare ability to smell what we eat while we eat it. This retronasal olfaction gives us a palate unrivalled in the animal kingdom, capable of discriminating between nearly two trillion savours: and ability which has all kinds of implications for memory and behaviour.

Is this a problem? Not at all. For all that it’s stuffed with entertaining oddities, Sentient is not a book about oddities, and Higgins’s argument, though colourful, is rigorous and focused. Over 400 exhilarating pages, she leads us to adopt an entirely unfamiliar way of thinking about the senses.

Because their mechanics are fascinating and to some degree reproduceable (the human eye is, mechanically speaking, very much like a camera) we grow up thinking of the senses as mechanical outputs.

Looking at our senses this way, however, is rather like studying fungi but only looking at the pretty fruiting bodies. The real magic of fungi is their networks. And the real magic of our senses is the more than 100 billion nerve cells in each human nervous system — greater, Higgins says, than the number of stars in the Milky Way.

And that vast complexity — adapting to reflect and organise the world, not just over evolutionary time but also over the course of an individual life — gives rise to all kinds of surprises. In some humans, the ability to see with sound. In vampire bats (who can sense the location of individual veins to sink their little fangs into), the ability to detect heat using receptors that in most other mammals are used to detect acute pain.

In De Anima, the ancient philosopher Aristotle really let the side down in listing just five senses. No one expects him to have spotted exotica like cuddlesomeness and where-to-face-when-you-pee. But what about pain? What about balance? What about proprioception?

Aristotle’s restrictive and mechanistic list left him, and generations after him, with little purchase on the subject. Insights have been hard to come by.

Aristotle himself took one look at the octopus and declared it stupid.

Let’s see him driving a car with eight legs.

Variation and brilliance

Reading Barnabas Calder’s Architecture: from prehistory to climate emergency for New Scientist, 9 June 2021

For most of us, buildings are functional. We live, work, and store things in them. They are as much part of us as the nest is a part of a community of termites.

And were this all there was to say about buildings, architectural historian Barnabas Calder might have found his book easier to write. Calder wants to ask “how humanity’s access to energy has shaped the world’s buildings through history.” And had his account remained so straightforward, we might have ended up with an eye-opening mathematical description of the increase the energy available for work — derived first from wood, charcoal and straw, then from coal, then from oil — and how it first transformed, and (because of global warming) now threatens our civilisation.

And sure enough the book is full of startling statistics. (Fun fact: the charcoal equivalent of today’s cement industry would have to cover an area larger than Australia in coppiced timber.)

But of course, buildings aren’t simply functional. They’re aspirational acts of creative expression. However debased it might seem, the most ordinary structure is a work of a species of artist, and to get built at all it must be bankrolled by people who are (at least relatively) wealthy and powerful. This was as true of the buildings of Uruk (our first known city, founded in what is now Iraq around 3200 BCE) as it is of the buildings of Shenzhen (in 1980 a Chinese fishing hamlet, today a city of nearly 13 million people).

While the economics of the build environment are crucially important, then, they don’t really make sense without the sociology, and even the psychology, especially when it comes to “the mutual stirring of hysteria between architect and client” that gave us St Peter’s Basilica in the 16th century and Chengdu’s New Century Global Center (currently the world’s biggest building) in the 21st.

Calder knows this: “What different societies chose to do with [their] energy surplus has produced endless variation and brilliance,” he says. So if sometimes his account seems to wander, this is why: architecture itself is not a wholly economic activity, and certainly not a narrowly rational one.

At the end of an insightful and often impassioned journey through the history of buildings, Calder does his level best to explain how architecture can address the climate emergency. But his advices and encouragements vanish under the enormity of the crisis. The construction and running of buildings account for 39 per cent of all human greenhouse gas emissions. Concrete is the most used material on Earth after water. And while there is plenty of “sustainability” talk in the construction sector, Calder finds precious little sign of real change. We still demolish too often, and build too often, using unsustainable cement, glass and steel.

It may be that solutions are out there, but are simply invisible. The history of architecture is curiously incomplete, as Calder himself acknowledges, pointing out that “entire traditions of impressive tent-like architecture are known mainly from pictures rather than physical remnants.”

Learning to tread more lightly on the earth means exactly that: a wholly sustainable architecture wouldn’t necessarily show up in the archaeological record. The remains of pre-fossil fuel civilisations can, then, only offer us a partial guide to what our future architecture should look like.

Perhaps we should look to existing temporary structures — to refugee camps, perhaps. The idea may be distressing, but fashions change.

Calder’s long love-poem to buildings left me, rather paradoxically, thinking about the Mongols of the 13th century, for whom a walled city was a symbol of bondage and barbarism.

They would have no more settled in a fixed house than they would have submitted to slavery. And their empire, which covered 23 million square kilometres, demolished more architecture than it raised.