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Now you see it, now you don't: what optical illusions tell us about our brains

Illusions can offer insights into how the visual system processes images.

Maurits Escher: where do the staircases lead?

The human brain is a network of about 20 billion neurons – nerve cells – linked by several trillion connections. Not to mention glial cells, which scientists used to think were inactive scaffolding, but increasingly view as an essential part of how the brain works. Our brains give us movement, language, senses, memories, consciousness and personality. We know a lot more about the brain than we used to, but it still seems far too complicated for human understanding.

Fortunately, the brain contains many small networks of neurons that carry out some specific function: vision, hearing, movement. It makes sense to tackle these simple modules first. Moreover, we have good mathematical models of nerve cell behaviour. In 1952, Alan Hodgkin and Andrew Huxley wrote down the “Hodgkin-Huxley equations” for the transmission of a nerve impulse, which won them the 1963 Nobel Prize in Medicine. We also have effective techniques for understanding small networks’ components and how they are linked.

Many of these simple networks occur in the visual system. We used to think that the eye was like a camera, taking a “snapshot” of the outside world that was stored in the brain like a photo stuck in an album. It uses a lens to focus an image on to the retina at the back of the eye, which functions a bit like a roll of film – or, in today’s digital cameras, a charge-coupled device, storing an image pixel by pixel. But we now know that when the retina sends information to the brain’s visual cortex, the similarity to a camera ends.

Although we get a strong impression that what we are seeing is “out there” in front of us, what determines that perception resides inside our own heads. The brain decomposes images into simple pieces, works out what they are, “labels” them with that information, and reassembles them. When we see three sheep and two pigs in a field, we “know” which bits are sheep, which are pigs, and how many of each there are. If you try to program a computer to do that, you quickly realise how tricky the process is. Only very recently have computers been able to distinguish between faces, let alone sheep and pigs.

Probing the brain’s detailed activity is difficult. Rapid progress is being made, but it still takes a huge effort to get reliable information. But when science cannot observe something directly, it infers it, working indirectly. An effective way to infer how something functions is to see what it does when it goes wrong. It may be hard to understand a bridge while it stays up, but you can learn a lot about strength of materials when it collapses.

The visual system can “go wrong” in several interesting ways. Hallucinogenic drugs can change how neurons behave, producing dramatic images such as spinning spirals, which originate not in the eye, but in the brain. Some images even cause the brain to misinterpret what it’s seeing without outside help. We call them optical illusions.

One of the earliest was discovered in Renaissance Italy in the 16th century. Giambattista della Porta was the middle of three surviving sons of a wealthy merchant nobleman who became secretary to the Holy Roman emperor Charles V. The father was an intellectual, and Giambattista grew up in a house in Naples that hosted innumerable mathematicians, scientists, poets and musicians. He became an outstanding polymath, with publications on secret codes (including writing on the inside of eggshells), physiology, botany, agriculture, engineering, and much else. He wrote more than 20 plays.

Della Porta was particularly interested in the science of light. He made definitive improvements to the camera obscura, a device that projects an image of the outside world into a darkened room; he claimed to have invented the telescope before Galileo, and very likely did. His De refractione optices of 1593 contained the first report of a curious optical effect. He arranged two books so that one was visible to one eye only and the other to the other eye. Instead of seeing a combination of the two images, he perceived them alternately. He discovered that he could select either image at will by consciously switching his attention. This phenomenon is known today as binocular rivalry.

Two other distinct but related effects are impossible figures and visual illusions. In rivalry, each image appears unambiguous, but the eyes are shown conflicting images. In the other two phenomena, both eyes see the same image, but in one case it doesn’t make sense, and in the other it makes sense but is ambiguous.

Impossible figures at first sight seem to be entirely normal, but depict things that cannot exist – such as Roger Shepard’s 1990 drawing of an elephant in which everything above the knees makes sense, and everything below the knees makes sense, but the two regions do not fit together correctly. The Dutch artist Maurits Escher made frequent use of this kind of visual quirk.

In 1832, the Swiss crystallographer Louis Necker invented his “Necker cube” illusion, a skeletal cube that seems to switch its orientation repeatedly. An 1892 issue of the humorous German magazine Fliegende Blätter contains a picture with the caption “Which animals are most like each other?” and the answer “Rabbit and duck”. In a 1915 issue of the American magazine Puck, the cartoonist Ely William Hill published “My wife and my mother-in-law”, based on an 1888 German postcard. The image can be seen either as a young lady looking back over her shoulder, or as an elderly woman facing forwards. Several of Salvador Dalí’s paintings include illusions; especially Slave Market With the Apparition of the Invisible Bust of Voltaire, where a number of figures and everyday objects, carefully arranged, combine to give the impression of the French writer’s face.

Illusions offer insights into how the visual system processes images. The first few stages are fairly well understood. The top layer in the visual cortex detects edges of objects and the direction in which they are pointing. This information is passed to lower layers, which detect places where the direction suddenly changes, such as corners. Eventually some region in the cortex detects that you are looking at a human face and that it belongs to Aunt Matilda. Other parts of the brain are alerted, and you belatedly remember that tomorrow is her birthday and hurry off to buy a present.

These things don’t happen by magic. They have a very definite rationale, and that’s where the mathematics comes in. The top layer of the visual cortex contains innumerable tiny stacks of nerve cells. Each stack is like a pile of pancakes, and each pancake is a network of neurons that is sensitive to edges that point in one specific direction: one o’clock, two o’clock and so on.

For simplicity, call this network a cell; it does no harm to think of it as a single neuron. Roughly speaking, the cell at the top of the stack senses edges at the one o’clock position, the next one down corresponds to the two o’clock angle, and so on. If one cell receives a suitable input signal, it “fires”, telling all the other cells in its stack: “I’ve seen a boundary in the five o’clock direction.” However, another cell in the same stack might disagree, claiming the direction is at seven o’clock. How to resolve this conflict?

Neurons are linked by two kinds of connection, excitatory and inhibitory. If a neuron activates an excitatory connection, those at the other end of it are more likely to fire themselves. An inhibitory connection makes them less likely to fire. The cortex uses inhibitory connections to reach a definite decision. When a cell fires, it sends inhibitory signals to all of the other cells in its stack. These signals compete for attention. If the five o’clock signal is stronger than the seven o’clock one, for instance, the seven o’clock one gets shut down. The cells in effect “vote” on which direction they are detecting and the winner takes all.

Many neuroscientists think that something very similar is going on in visual illusions and rivalry. Think of the duck and rabbit with two possible interpretations. Hugh R Wilson, a neuroscientist at the Centre for Vision Research at York University, Toronto, proposed the simplest model, one stack with just two cells. Rodica Curtu, a mathematician at the University of Iowa, John Rinzel, a biomathematician then at the National Institutes of Health, and several other scientists have analysed this model in more detail. The basic idea is that one cell fires if the picture looks like a duck, the other if it resembles a rabbit. Because of the inhibitory connections, the winner should take all. Except that, in this illusion, it doesn’t quite work, because the two choices are equally plausible. That’s what makes it an illusion. So both cells want to fire. But they can’t, because of those inhibitory connections. Yet neither can they both remain quiescent, because the incoming signals encourage them to fire.

One possibility is that random signals coming from elsewhere in the brain might introduce a bias of perception, so that one cell still wins. However, the mathematical model predicts that, even without such bias, the signals in both cells should oscillate from active to inactive and back again, each becoming active when the other is not. It’s as if the network is dithering: the two cells take turns to fire and the network perceives the image as a duck, then as a rabbit, and keeps switching from one to the other. Which is what happens in reality.

Generalising from this observation, Wilson proposed a similar type of network that can model decision-making in the brain – which political party to support, for instance. But now the network consists of several stacks. Maybe one stack represents immigration policy, another unemployment, a third financial regulation, and so on. Each stack consists of cells that “recognise” a distinct policy feature. So the financial regulation stack has cells that recognise state regulation by law, self-regulation by the industry, or free-market economics.

The overall political stance of any given political party is a choice of one cell from each stack – one policy decision on each issue. Each prospective voter has his or her preferences, and these might not match those of any particular party. If these choices are used as inputs to the network, it will identify the party that most closely fits what the voter prefers. That decision can then be passed to other areas of the brain. Some voters may find themselves in a state akin to a visual illusion, vacillating between Labour and Liberal Democrat, or Conservative and Ukip.

This idea is speculative and it is not intended to be a literal description of how we decide whom to vote for. It is a schematic outline of something more complex, involving many regions of the brain. However, it provides a simple and flexible model for decision-making by a neural network, and in particular it shows that simple networks can do the job quite well. Martin Golubitsky of the Mathematical Biosciences Institute at Ohio State University and Casey O Diekman of the University of Michigan wondered whether Wilson’s networks could be used to model more complex examples of rivalry and illusions. Crucially, the resulting models allow specific predictions about experiments that have not yet been performed, making the whole idea scientifically testable.

The first success of this approach helped to explain an experiment that had already been carried out, with puzzling results. When the brain reassembles the separate bits of an image, it is said to “bind” these pieces. Rivalry provides evidence that binding occurs, by making it go wrong. In a rivalry experiment carried out in 2006 by S W Hong and S K Shevell, the subject’s left eye is shown a horizontal grid of grey and pink lines while the right eye sees a vertical grid of grey and green lines. Many subjects perceive an alternation between the images, just as della Porta did with his books. But some see two different images alternating: pink and green vertical lines, and pink and green horizontal lines – images shown to neither eye. This effect is called colour misbinding; it tells us that the reassembly process has matched colour to grid direction incorrectly. It is as if della Porta had ended up seeing another book altogether.

Golubitsky and Diekman studied the simplest Wilson network corresponding to this experiment. It has two stacks: one for colour, one for grid direction. Each stack has two cells. In the “colour” stack one cell detects pink and the other green; in the “orientation” stack one cell detects vertical and the other horizontal. As usual, there are inhibitory connections within each stack to ensure a winner-takes-all decision.

Following Wilson’s general scheme, they also added excitatory connections between cells in distinct stacks, representing the combinations of colour and direction that occur in the two “learned” images – those actually presented to the two eyes. Then they used recent mathematical techniques to list the patterns that arise in such a network. They found two types of oscillatory pattern. One corresponds to alternation between the two learned images. The other corresponds precisely to alternation between the two images seen in colour misbinding.

Colour misbinding is therefore a natural feature of the dynamics of Wilson networks. Although the network is “set up” to detect the two learned images, its structure produces an unexpected side effect: two images that were not learned. The rivalry experiment reveals hints of the brain’s hidden wiring. The same techniques apply to many other experiments, including some that have not yet been performed. They lead to very specific predictions, including more circumstances in which subjects will observe patterns that were not presented to either eye.

Similar models also apply to illusions. However, the excitatory connections cannot be determined by the images shown to the two eyes, because both eyes see the same image. One suggestion is that the connections may be determined by what your visual system already “knows” about real objects.

Take the celebrated moving illusion called “the spinning dancer”. Some observers see the solid silhouette of a dancer spinning anticlockwise, others clockwise. Sometimes, the direction of spin seems to switch suddenly.

We know that the top half of a spinning dancer can spin either clockwise or anticlockwise. Ditto for the bottom half. In principle, if the top half spins one way but the bottom half spins the other way, you would see the same silhouette, as if both were moving together. When people are shown “the spinning dancer”, no one sees the halves moving independently. If the top half spins clockwise, so does the bottom half.

Why do our brains do this? We can model that information using a series of stacks that correspond to different parts of the dancer’s body. The brain’s prior knowledge sets up a set of excitatory connections between all cells that sense clockwise motion, and another set of excitatory connections between all “anticlockwise” cells. We can also add inhibitory connections between the “clockwise” and the “anticlockwise” cells. These connections collectively tell the network that all parts of the object being perceived must spin in the same direction at any instant. Our brains don’t allow for a “half and half” interpretation.

When we analyse this network mathematically, it turns out that the cells switch repeatedly between a state in which all clockwise cells are firing but the anticlockwise ones are quiescent, and a state in which all anticlockwise cells are firing but the clockwise ones are quiescent. The upshot is that we perceive the whole figure of the dancer switching directions. Similar networks provide sensible models for many other illusions, including some in which there are three different inputs.

These models provide a common framework for both rivalry and illusion, and they unify many experiments, explain otherwise puzzling results and make new predictions that can be tested. They also tell us that in principle the brain can carry out some apparently complex tasks using simple networks. (What it does in practice is probably different in detail, but could well follow the same general lines.)

This could help make sense of a real brain, as new experiments improve our ability to observe its “wiring diagram”. It might not be as ambitious as trying to model the whole thing on a computer, but modesty can be a virtue. Since simple networks behave in strange and unexpected ways, what incomprehensible quirks might a complicated network have?

Perhaps Dalí, and Escher, and the spinning dancer can help us find out. 

Ian Stewart is Emeritus Professor of Mathematics and Digital Media Fellow at the University of Warwick

ANDRÉ CARRILHO
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The Great Huckster: Boris Johnson’s reckless distortions of history

As a scholar of Churchill, Boris Johnson could have articulated a constructive vision for Britain and Europe. Instead, he wilfully manipulates and distorts the historical record.

This month, 76 years ago, the defeated British Expeditionary Force was making for the Channel ports. Thanks to the ferocious resistance put up by the garrison at Calais, and Hitler’s hesitation, the bulk of the men were safely taken off the beaches at Dunkirk to fight another day. Whatever their private feelings during those terrible hours may have been, most of them knew even then that they would return to Europe to finish the job.

Their forefathers had been intervening in Europe for as long as anyone could remember. From Shakespeare’s Henry V through to Elizabeth’s support for the Dutch revolt, the Second Hundred Years War against Louis XIV, the French Revolution and Napoleon, and the First World War, London had always been profoundly invested in the continent. Defending the “liberties of Europe” and thus British freedoms was what Englishmen and Britons did. It was part of what they were.

In early June 1944 – on D-Day – the British, Americans and Canadians hurled themselves into northern France as their ancestors had done since the late Middle Ages. At least one British officer tried to inspire his men that morning as the landing craft approached the strongly defended beaches by reading out Henry V’s speech before Harfleur, in which Shakespeare has him exhort the men, “once more unto the breach”. The film version of the play was released that same year, dedicated to the “commando and airborne troops of Great Britain”. In the popular mind, these Englishmen and their North American descendants were part of the continuity of a European story that went back to the medieval English empire in France.

Some of those liberating Europe thought that they could not simply return to “business as usual” after the war. One of them was the later Conservative prime minister Ted Heath, the man who took Britain into the European Economic Community in 1973. He first defended Liverpool as an anti-aircraft gunner and then took the fight to Hitler as an artillery man during the campaign in north-west Europe. Over the course of the next 11 months, Heath and his comrades fought their way across the traditional battlefields of northern France and the Low Countries, including the Walcheren swamps in which their ancestors had been mired in Napoleonic times; and through western Germany into the centre of the Reich. They were to stay there, at the heart of Europe, for some 60 years. They created a stable European order, based on Nato and what was to become the European Union, which remains with us to this day.

Now the Brexit stalwart Boris Johnson, my fellow historian, claims that it was all in vain. “The European Union,” he says, “is an attempt to do what Hitler wanted by different methods.” Worse still, the EU is a German plot, whose currency, the euro, was “intended by the Germans” to “destroy” Italian manufacturing and generally grind the faces of its unfortunate members. Johnson has also invoked the spirit of Churchill in support of his arguments. He has since doubled down on his remarks and has received support from other members of the Brexit camp, such as Iain Duncan Smith, though not apparently from more informed figures such as Michael Gove. Unfortunately, Johnson’s claims are as historically wrong as it is possible to be, comparable in their crassness only to his predecessor as London mayor Ken Livingstone’s suggestion that Hitler supported Zionism.

Far from supporting European political unity, Hitler was violently and explicitly opposed to the idea. This was partly because it was proposed by his opponents on the “left” of the Nazi Party, such as the Strasser brothers. They belonged to the “anti-imperialist” wing of the Nazi Party, which wanted a pan-European front against the Jews and the British empire. Hitler’s hostility to the European project was also in part due to a racial antipathy to the half-Japanese Richard, Count Coudenhove-Kalergi, the author of the widely discussed book Pan-Europa (1923). One way or the other, Hitler condemned the Pan-Europa movement as “a fantastical, historically impossible childishness”, which would be no more than a “Jewish protectorate”.

Nor did he hold back with his alternative view of what the continent should look like. “The solution,” he wrote, “cannot be Pan-Europa, but rather a Europe of free and independent national states, whose spheres of interest are separate and clearly delineated.” Comparisons involving Hitler are usually odious but if one is going to draw parallels, his view of European integration then was much closer to that of the Brexiters today than that of the advocates of the European Union.

Moreover, the European project did not originate in the Nazis’ attempt to mobilise the continent on their behalf but rather in the resistance movement against Hitler. Take Sicco Mansholt, who hid Dutch resisters on his farm during the war, at great personal risk. He subsequently became the Dutch minister for agriculture and one of the fathers of the Common Agricultural Policy (CAP). Take Altiero Spinelli, the Italian anti-fascist who spent ten years in Mussolini’s prisons. It was there, in June 1941, at the height of Hitler’s power, that he secretly wrote his draft manifesto For a Free and United Europe.

Take Paul-Henri Spaak, later prime minister of Belgium, first president of the Common Assembly of the European Coal and Steel Community – the forerunner of the EU – and secretary-general of Nato. He was forced to make a daring escape from wartime Europe in the false bottom of a lorry in order to carry on the struggle against Hitler in exile. Indeed, across Europe there were thousands of men and women who fought, died, were imprisoned or tortured because they believed in a free and united Europe. To suggest that they were trying to achieve the same thing as Hitler by different methods is an outrageous slur on their memory. If Johnson ever makes it to the top of the Conservative Party, and thence to No 10, he will have a lot of explaining and apologising to do in Europe.

***

As if all this were not bad enough, Boris Johnson’s invocation of Churchill flies in the face of everything we know of the great man’s attitude to the European project. To be sure, he began as a Eurosceptic. When army reforms were proposed in 1901 to support the creation of a substantial land force on the continent, the young Winston Churchill was one of the few MPs to oppose them on the grounds that the navy, rather than the army, was of crucial importance to British security. Writing in the Morning Post, Churchill argued that “history” and “geography” showed that the British empire was “essentially commercial and marine”, and had been defended by armies of foreigners.

As the German threat loomed large, however, he changed his mind. Churchill, then first lord of the admiralty, told the Australians and New Zealanders in April 1913 that Europe was “where the weather came from”. It was the terrible storm of the First World War that caused Churchill not only to believe in the centrality of Europe but in the need for European – or at least continental European – unity.

In May 1930, the president of the Pan-Europa Union, the former French prime minister Aristide Briand, made a formal proposal for a “European federal union” based on a “European conference” with an executive to co-ordinate economic and military co-operation. The British government of the time rejected the surrender of sovereignty involved but many were sympathetic to the idea of continental European union under liberal auspices. The arch-imperialist Leo Amery, secretary of state for the colonies and later a powerful critic of appeasement, was a strong admirer of Coudenhove and his projects, which he regarded as the extension of Anglo-Saxon principles to the continent.

Likewise, Churchill, then chancellor of the Exchequer, told parliament in June 1925 that he hoped that one could “weave Gaul and Teuton so closely together economically, socially and morally as to prevent the occasion of new quarrels and make old antagonisms die in the realisation of mutual prosperity and interdependence”. Then, he continued, “Europe could rise again”. Churchill did not believe, however, that Britain should be part of any continental political union. “We are with Europe, but not of it,” he wrote in 1930. “We are linked but not compromised. We are interested and associated but not absorbed.”

In mid-June 1940, however, as western Europe buckled under the Nazi onslaught, Churchill went a step further. He made an unsuccessful offer of union with France – involving joint citizenship and a common government – designed to lock the French into the war effort against Germany or, failing that, to secure their fleet. The Nazi threat was so existential, in other words, that it justified the surrender, or at least the pooling, of British sovereignty.

When the threat of invasion passed, Churchill returned to the theme of continental European integration. In October 1942, he “look[ed] forward to a United States of Europe in which barriers between the nations will be greatly minimised. He “hope[d] to see the economy of Europe studied as a whole”, and the establishment of a council of “ten units, including the former Great Powers [and thus presumably Britain], with several confederations – Scandinavian, Danubian, Balkan, etc, which would possess an international police and be charged with keeping Prussia disarmed”.

Churchill returned to the subject immediately after the war, as the Soviet threat menaced Europe. In a speech at Zurich University in September 1946, he urged the continent to “unite”, with Britain supporting the project from the outside. Once again, including the Germans was central to his conception. Churchill urged no less than the full political union of the continent in a “kind of United States of Europe” under the “principles embodied in the Atlantic Charter”. He again praised the work of Hitler’s bugbear, Count Coudenhove-Kalergi’s “Pan-European Union”.

Churchill demanded an “act of faith”, beginning with “a partnership between France and Germany”, assembling around them the states of Europe “who will and . . . can” join such a union. Its purpose was clear, namely “to make the material strength of a single state less important. Small nations will count as much as large ones and gain their honour by their contribution to the common cause.”

Moreover, Churchill argued, “The ancient states and principalities of Germany, freely joined together for mutual convenience in a federal system, might each take their individual place among the United States of Europe.” In short, the new polity was designed to solve not merely the European question but the German problem, the two being one and the same. Once again, Churchill conceived of this United States of Europe alongside but not including the United Kingdom and the British “Commonwealth of Nations”, that is, the empire. Instead, he believed that Britain should be one of the “sponsors of the new Europe”.

Churchill’s attitude to continental European union was, unlike Hitler’s, highly positive. For Johnson to suggest, therefore, that he is donning the mantle of Churchill to prevent the current European Union from achieving Hitler’s aims through other means is a complete travesty of the historical truth.

Far from being intended to promote German power, the European Union was designed to contain it, or at least to channel it in the right direction. Contrary to what Johnson suggests, the euro was not planned by Germany to subjugate Italian industry or any other European economy. It was insisted on by the French to decommission the deutschmark, which they described as Germany’s “nuclear weapon”. Likewise, the Germans are not incarcerating the Greeks in their European prison: Greeks are desperate not to be released back into the “freedom” of the drachma and the corrupt national politics that they joined “Europe” to escape. If there is one thing worse than being dominated by Germany in the European Union, evidently, it is not being in the EU at all.

Boris Johnson may not have known the details of Hitler’s attitude to European integration, or the European sympathies of many resisters, but he is very well informed about Churchill and Europe. His ignorance is thus not just a matter of making mistakes; we all make those as historians. Nor is it simply a matter of these mistakes being, like bank errors, in favour of one’s own argument. To say that Johnson knows better is not a figure of speech: he has shown in print that he does. His recent book, The Churchill Factor, contains a very balanced account of Churchill’s position on Europe, including most of the statements listed above.

In making his arguments, Johnson is not appealing to the baser instincts of the electorate; it is far worse than that. The deeply ingrained British instinct to fight European tyranny is not base but fine. What Johnson and those who defend his rhetoric have done is to take something virtuous and pervert it. The European Union is not, as we have seen, the continuation of Hitlerism by other means and to suggest so is blatant manipulation.

The shame of it is that there is a perfectly plausible Eurosceptic argument on its own merits. It was well stated by Michael Gove at the start of the campaign. It insists on the historical distinctiveness of the United Kingdom, whose history does indeed set it apart from the rest of the continent. It makes the case for a reform of the EU. It rejects the scaremongering of “Project Fear”, on the cogent grounds that the United Kingdom has the political, economic and military weight to prevail even without the stabilisers of the EU. It scorns President Obama’s impertinent warning that Britain would have to “get to the back of the queue” for a trade deal after Brexit, with a reminder that Britain and her empire defied Nazi Germany for two years before the Americans joined the fray, when Hitler declared war on them (not vice versa). One does not have to accept every detail of this discourse to feel its force. Uniquely among the democratic European powers, the United Kingdom can “stand alone” if it must or wants to.

The Achilles heel of the Brexit campaign, however, is that it has no viable vision for continental Europe. Even Gove falls down here, as his idea of a British departure unleashing a “democratic liberation” of the continent is pure fantasy. It seems odd to have to explain this to Brexiters but Britain really is special. Casting off the bonds of Brussels will not emancipate mainland Europe but let loose the nationalist and xenophobic demons tamed by the integration project. This is clear when we look at the rise of radical anti-European parties in France, Hungary, Austria, Germany and many other parts of Europe as the European project fragments. These developments should not surprise anyone who knows the history of mainland Europe before the mid-20th century and to a considerable sense beyond.

***

 

Most of continental Europe had failed before 1945 and even now the European Union is only failing better. Unlike virtually every other European state, which has at some point or other been occupied and dismembered, often repeatedly, England and the United Kingdom have largely – with very brief exceptions – been subjects of European politics, never merely objects. In this sense, too, she is exceptional. Yet this should not be an occasion for British triumphalism. Whatever the outcome of the referendum on 23 June, the European Union is not an enemy of the United Kingdom. It should best be understood as a modern version of the old Holy Roman Empire; hapless and officious, perhaps, but not malign. It needs help. The failure of the European project and the collapse of the current continental order would be not only a catastrophic blow to the populations on the far side of the Channel but also to the United Kingdom, which would be
directly exposed to the resulting disorder, as it always has been.

In short, the Brexit camp in general and Boris Johnson in particular are missing a great opportunity in Europe. A student and partisan of Winston Churchill, the former mayor of London was qualified to articulate a constructive vision for Britain and the continent. He has failed to understand that the only safe way that Britain can exit from the European Union is not through Brexit – whose consequences for mainland Europe would be dire – but through Euroexit; that is, a Churchillian political union of the continent in close co-operation with the UK.

Instead, in addition to their distortion of the historical record, Johnson and the Brexit camp are committing the cardinal sin of making a decision before they need to. The European Union is not, sadly, a United States of Europe, even though it needs to become one to survive, and is becoming less like one every day. If and when it musters the strength for full political union, there will be plenty of time to leave. Meanwhile, the EU needs all the support that Britain can give it from within.

In 1940, the British forces had been defeated and retreat was the only option. The situation could not be more different today. This is no time to head for the beaches in what will be a legislative Dunkirk of epic proportions, with incalculable consequences not so much for Britain as for the rest of the continent. Unlike in 1940, the United Kingdom is not being forced out of Europe. It has hardly begun to fight there, unless shooting oneself in the foot through Brexit counts as combat. The battle in Britain today is a distraction from the great struggle on the mainland. There is much work to be done in Europe. It is time the British stop tearing themselves apart and return unto the breach once more.

Brendan Simms is a NS contributing writer. His latest book is “Britain’s Europe: a Thousand Years of Conflict and Co-operation” (Allen Lane). He is president of the Project for Democratic Union

This article first appeared in the 19 May 2016 issue of the New Statesman, The Great Huckster