Worlds within worlds: Outpost (2007) by the artist Anne Hardy. Photograph: Anne Hardy, courtesy of Maureen Paley, London
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Terry Pratchett, science and story telling

The best of all possible worlds.

Terry Pratchett’s first Discworld novel was published in 1983. As a wartime child in the 1940s I was already puzzling over an image of a domed world poised on the backs of three elephants that stood on a monstrous turtle. This discworld had a small temple on top of it, and the clawed feet of the turtle rested on the coils of a huge serpent, which also stretched to encircle the world, with the point of its tail in its mouth. It was reproduced in my favourite book, Asgard and the Gods, a scholarly German work on Norse myths, which my mother had used at Cambridge.

This image, and this book, provoked my earliest thinking about the nature of belief and its relation to storytelling. Where on earth did the idea of the turtle and the elephants come from? Did people really believe in them? These questions were related to the kind of embarrassed pain with which I contemplated the stories of origins I was expected to believe in, the Bible with its heaven and hell, the tale of judgement to come.

Pratchett’s new book, The Science of Discworld IV, co-written with the mathematician Ian Stewart and the biologist Jack Cohen, discusses ideas about origins and endings, cosmology and astrobiology, entropy and genetics. The idea of storytelling is not just an embroidered way of including a tale of the discussion of the “Roundworld” taking place on the Discworld. Human beings are defined as pan narrans, the storytelling ape, who exists in a dimension known as the “narrativium”. We look for causes because we think in linear sequences of words. We look for origins because we arrange our world into narrative strings with beginning, middle and end. Stewart, Cohen and Pratchett set out to puzzle us and make us think differently.

Central to their approach is the distinction made by the physicist and sciencefiction author Gregory Benford between human-centred thinking and universecentred thinking. Human-centred thinking comes naturally to human beings. “In this world-view, rain exists in order to make crops grow and to provide fresh water for us to drink. The sun is there because it warms our bodies.” From human-centred thinking comes the idea of a ruler of the universe, as well as the idea that the earth and the creatures, the sea and the oil and the forests are somehow there for our benefit. Universe-centred thinking, on the other hand, sees human beings as “just one tiny feature of a vast cosmos, most of which does not function on a human scale or take any notice of what we want”. The universecentred thinker must have what Keats called “negative capability” – the capacity to be in uncertainties, mysteries, doubts, without any irritable reaching after fact and reason. This is hard and invigorating.

The writers discuss creation myths – including a number of myths about cosmic turtles and scientific ideas about origins, including the Big Bang. They discuss the evolution of ideas about evolution, recent thoughts about the relation of RNA to DNA and the idea of the curvature of space. They also consider neural networks and decision theory, and the strong and weak anthropic principles – ideas about how the physical universe is uniquely suited to the existence of human beings.

Pratchett and co also explore the psychology of belief and disbelief. They describe one way of coming to conclusions – the brain taking in new evidence, and fitting it to the knowledge and beliefs it already holds. This is what they call “System 1”, and it includes scientific thinkers as well as people with inherited religious beliefs. There are, they say, scientists who “know” that DNA is the most important part of the system, physicists who “know” that the world is moving towards entropy. “System 2”, on the other hand, is steadily analytical and sceptical – “trying, not always successfully, to ignore inbuilt prejudices”. Karl Popper’s system of “critical rationalism” held that a theory could be considered scientific if, and only if, it was capable of falsification. Stewart and Cohen claim that “scientists actively try to disprove the things they would like to be true”. They use the example of a believer in UFOs who sees disbelief in UFOs as another form of belief. “Zero belief in UFOs”, they point out, is not the same as 100 per cent belief in the non-existence of UFOs. “Zero belief is an absence of belief, not an opposed form of belief.” What they aspire towards and desire is “a disbelief system”. This is exhilarating.

I remember being on a platform where various poets and writers discussed the ways in which the arts could figure the world of the scientist. That blunt sceptic Lewis Wolpert, sitting in the audience, rose to inform the assembled artists that we would not understand any of his work were we to find ourselves in his laboratory. Some of us were indignant but I believe he was right. People like me can read what is written by those scientists who try to tell us about neurons, genes, the shape of the brain, the shape of space and time. We can respond to those descriptions but we are responding to stories, at second hand.

One of the most pleasing things about Pratchett, Stewart and Cohen’s book is the way the authors demonstrate that we don’t understand even what we think we understand. I realised, reading their account of the complex relations between RNA and DNA, that I had been guilty of holding a belief. I was very excited in the late 1970s by ideas about the “selfish gene”, and particularly by the points made by John Maynard Smith about the immutable nature of the inherited and eternal germ cell. Now the New Scientist is full of articles about newly discovered “orphan DNA”. Stewart and Cohen write:

Darwin’s tree of life, a beautiful idea that derives from a sketch in The Origin of Species and has become iconic, gets very scrambled around in its roots because of a process called horizontal gene transfer. Bacteria, archaea and viruses swap genes with gay abandon, and they can also insert them into the genomes of higher animals, or cut them out. So a gene in one type of bacterium might have come from another type of bacterium altogether, or from an archaean, or even from an animal or a plant.

The story I believed in has to be modified and rethought. When I read this, I think in a human way with a series of images, in the grammar of a story. I should not be able to recognise any gene, let alone think intelligently about it. Stewart and Cohen are very good at illustrating our incapacity to understand. They do so with images and stories. My favourite is the one they tell to make us think about the difference between complicated chemistry and the “organised complexity” of the ribosome. It is a story about caramel.

Every cook knows that heating sugar with fats, two fairly simple chemical substances, produces caramel . . .  Caramel is enormously complicated on a chemical level. It includes innumerable different molecules, each of which has thousands of atoms. The molecular structure of caramel is far more complicated than most of the molecules you’re using to read this page.

But the complexity of caramel, or other complicated polymers, doesn’t produce organised complexity, as ribosomes do. Wolpert would rightly tell me that I still don’t know anything about the ribosomes. But I am at least able now to think about the problem. And the juxtaposition of caramel and brain is unforgettable. There are delights like this on most pages of this book.

In a chapter entitled “Where did that come from?” we are invited to reflect on how we can’t think about things like the origin of an oak tree, or a child, or even a thunderstorm. They make the reader imagine thinking about clouds, the constituents of the atmosphere, static electricity, physics and physical chemistry. Most of us, they say, “will not have come across one or more phrases such as ‘saturated solution’ or ‘particle carries a tiny electrical charge’. These phrases are themselves simplifications of concepts with many more associations, and more intellectual depth, than anyone can be expected to generate for themselves.” Human beings tend to retreat from uncertainty or difficulty into belief stories, like the American Republican candidate who opposed any regulation of the markets on the grounds that this was “interfering with God’s plan for the American economy”.

Pratchett, Stewart and Cohen use their method of complicating descriptions and explanations to examine several problems with things I have trouble with believing myself, because they feel to me like human stories that tidy up our relation to the universe – the Big Bang, the existence of dark matter, entropy and the “anthropic principle”. They discuss conflicting views of the expanding universe and the steady state and cast doubt on the existence of dark matter. They are not propounding or supporting any particular theory of the shape and origins of the universe, but are rather considering evidence that complicates the explanations we have become used to. They are good at picking out the operations of what they call our “very parochial” minds, which use ideas of space and time that evolved with us. “Our view of the universe may be just as parochial as the world-bearing animals of ancient cultures were. Future scientists may view both the Big Bang and four elephants riding on a turtle as conceptual errors of a very similar kind.”

In Richard Feynman’s The Character of Physical Law, they find a tendency evident in “too many physicists” to consider physical reality to be all of reality. Feynman, they write, states that “the same kind of atoms appear to be in living creatures as in non-living creatures [sic]; frogs are made of the same ‘goup’ as rocks only in different arrangements”. Things in the biological world are the results of the behaviour of physical and chemical phenomena with no “extra something.” Stewart and Cohen agree about the “no extra something” but think that a bleak view of the world of particles and elements misses out the complexity of living things, and the things they make and use and learn from.

Entropy may not be our destiny – they see Feynman rather as Pratchett sees his undifferentiated auditors, who want to tidy everything up into packets of particles. Life, say Stewart and Cohen, has “lifted itself up into a story”. That is a metaphor – and an attractive one. It feels right, and should therefore be regarded with the necessary doubt and suspicion. They also take a mocking run at the idea of “fine-tuning”, the idea that the world has evolved as the only possible world in which humans could exist – just the right amount of carbon and water, and so on.

This “anthropic principle”, in both its strong and its weak forms, has always horrified me because it is so clearly a function of the human mind thinking in a humancentred way. Isn’t it amazing, say the Discworld scientists, that our legs are just long enough to reach the ground? Isn’t it amazing that there was a hole exactly the right size to contain that puddle? And what about a sulphur-centred form of thought?

There was one chapter I found hard to understand – on the curvature of space, round worlds and disc worlds. This was where I wished the book had illustrations – I read pages about the doughnut-shaped torus, and then had the sense to consult Wikipedia, where I could see what was being discussed. And I also needed to see the geometry of the wonderful Escher image of angels and demons.

I have become rather sad about surviving into the anthropocene age of human history, where everything is controlled and constructed by and for what the King of Brobdingnag called “the most pernicious race of little odious vermin that Nature ever suffered to crawl upon the surface of the earth”. But, paradoxically, both Pratchett’s storytelling and the resolutely universecentred perspective of the scientists make me happier to be human. I look forward to the next volume.

“The Science of Discworld IV: Judgement Day” by Terry Pratchett, Ian Stewart and Jack Cohen is published by Ebury Press (£18.99). A S Byatt’s most recent book is “Ragnarok: the End of the Gods” (Canongate, £7.99

Both A S Byatt and Terry Pratchett will be appearing at How the Light Gets In, the festival of philosophy and music in Hay on Wye. For more details, visit:

This article first appeared in the 12 April 2013 issue of the New Statesman, Centenary Special Issue

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When it comes to responding to Islamic State, there is no middle ground

If Britain has a declared interest in curtailing Islamic State and stabilising Syria, it is neither honourable nor viable to let others intervene on our behalf.

Even before the brutal terrorist attacks in Paris, British foreign policy was approaching a crossroads. Now it is time, in the words of Barack Obama, addressing his fellow leaders at the G20 Summit in Turkey on 16 November, “to step up with the resources that this fight demands”, or stand down.

The jihadist threat metastasises, and international order continues to unravel at an alarming rate. A Russian civilian charter plane is blown out of the sky over the Sinai Peninsula in Egypt, killing 224 people, most of them returning from holiday, and the various offshoots of Islamic State bare their teeth in a succession of brutal attacks in France, Lebanon, Tunisia, Turkey and further afield. Our enemies are emboldened and our friends want to know to what extent we stand with them. The UK can no longer afford to postpone decisions that it has evaded since the Commons vote of August 2013, in which the government was defeated over the question of joining US-led air strikes against President Bashar al-Assad’s regime following a chemical weapons attack on Syrian civilians. MPs’ continued introspection is on the verge of becoming both irresponsible and morally questionable. There is no fence left to sit on.

On Sunday night, two days after the Paris attacks, the French – with US support – launched a series of bombing raids against Islamic State targets in Raqqa. With much more to come, the choice facing this country may not be easier but it is certainly clearer. Britain must determine whether it wants to be a viable and genuine partner in the fight against Islamic State, and in the long-term efforts to bring an end to the assorted evils of the Syrian civil war; or whether we are content to sit on the sidelines and cheer on former team-mates without getting our knees dirty. We can join our two most important allies – France and the United States, at the head of a coalition involving a number of Arab and other European states – in confronting a threat that potentially is as grave to us as it is to France, and certainly more dangerous than it is to the US. Alternatively, we can gamble that others will do the work for us, keep our borders tighter than ever, double down on surveillance (because that will certainly be one of the prices to pay) and hope that the Channel and the security services keep us comparatively safe. There is no fantasy middle ground, where we can shirk our share of the burden on the security front while leading the rest of the world in some sort of diplomatic breakthrough in Syria; or win a reprieve from the jihadists for staying out of Syria (yet hit them in Iraq), through our benevolence in opening the door to tens of thousands of refugees, or by distancing ourselves from the ills of Western foreign policy.

That the international community – or what is left of it – has not got its act together on Syria over the past three years has afforded Britain some space to indulge its scruples. Nonetheless, even before the Paris attacks, the matter was coming to the boil again. A vote on the expansion of air operations against Islamic State has been mooted since the start of this year, but was put on the back burner because of the May general election. The government has treated parliament with caution since its much-discussed defeat in the House in summer 2013. The existing policy – of supporting coalition air strikes against Islamic State in Iraq but not Syria – is itself an outgrowth of an awkward compromise between David Cameron and Ed Miliband, an attempt to reverse some of the damage done by the 2013 vote in parliament.

The Conservatives have waited to see where the ground lies in a Jeremy Corbyn-led Labour Party before attempting to take the issue back before the Commons. Labour pleaded for more time when Corbyn was elected, but there is no sign that the Labour leader is willing to shift in his hostility to any form of intervention. More significantly, he has now ruled out Labour holding a free vote on the matter.

If anything, the coalition of Little Englanders, anti-interventionists and anti-Americans in the House of Commons seems to have dug its trenches deeper. This leaves the Prime Minister with few options. One is to use the Royal Prerogative to announce that an ally has been attacked, and that we will stand with her in joining attacks against Islamic State in Syria. The moment for this has probably already passed, though the prerogative might still be invoked if Isis scores a direct hit against the UK. Yet even then, there would be problems with this line. A striking aspect of the killing of 30 Britons in the June attacks in Sousse, Tunisia, is just how little domestic political impact it seems to have made.

Another option for Cameron is to try to make one final effort to win a parliamentary majority, but this is something that Tory whips are not confident of achieving. The most likely scenario is that he will be forced to accept a further loss of the UK’s leverage and its standing among allies. Co-operation will certainly come on the intelligence front but this is nothing new. Meanwhile, the government will be forced to dress up its position in as much grand diplomatic verbiage as possible, to obfuscate the reality of the UK’s diminishing influence.

Already, speaking at the G20 Summit, the Prime Minister emphasised the need to show MPs a “whole plan for the future of Syria, the future of the region, because it is perfectly right to say that a few extra bombs and missiles won’t transform the situation”. In principle, it is hard to argue with this. But no such plan will emerge in the short term. The insistence that Assad must go may be right but it is the equivalent of ordering the bill at a restaurant before you have taken your seat. In practice, it means subcontracting out British national security to allies (such as the US, France and Australia) who are growing tired of our inability to pull our weight, and false friends or enemies (such as Russia and Iran), who have their own interests in Syria which do not necessarily converge with our own.

One feature of the 2013 Syria vote was the government’s failure to do the required groundwork in building a parliamentary consensus. Whips have spent the summer scouting the ground but to no avail. “The Labour Party is a different organisation to that which we faced before the summer,” Philip Hammond, the Foreign Secretary, has said. It is ironic, then, that the Prime Minister has faced strongest criticism from the Labour benches. “Everyone wants to see nations planning for increased stability in the region beyond the military defeat of the extremists,” says John Woodcock, the chairman of the Parliamentary Labour Party defence committee, “but after two years of pussy-footing around, this just smacks of David Cameron playing for time when he should be showing leadership.”

The real story is not the distance between the two front benches but the divisions within both parties. There are as many as 30 Conservative MPs said to be willing to rebel if parliament is asked to vote for joining the coalition against Islamic State in Syria. It seems that the scale of the Paris attacks has not changed their position. A larger split in the Labour ranks also seems likely. Even before Paris, there were rumoured to be roughly 50 MPs ready to defy their leader on this question.


At first, in the wake of last week’s attacks, it seemed as if the Prime Minister might force the issue. To this end, he began the G20 in Turkey with a bilateral meeting with President Putin. His carefully chosen words before and after that discussion, in which he was much more emollient about Moscow’s role, showed the extent to which he was prepared to adapt to the changing situation. Cameron hoped that if he could show progress in building an international coalition on the diplomatic front, that might just give him enough to get over the line in a parliamentary vote.

This new approach has not had the desired effect. At the time of writing, the government believes it is too risky to call another vote in the short term. It calculates another defeat would hugely diminish Britain’s standing in the world. In truth, the government was already swimming upstream. On 29 October, the Conservative-
dominated Commons foreign affairs select committee, chaired by Crispin Blunt, released a report on the extension of British military operations into Syria, in anticipation of government bringing forward a parliamentary vote on the question. The report recommended that Britain should avoid further involvement unless a series of questions could be answered about exit strategy and long-term goals. The bar was set deliberately high, to guard against any further involvement (even the limited option of joining the existing coalition undertaking air strikes against IS in Syria).

The most flimsy of the five objections to further intervention in the report was that it will somehow diminish the UK’s leverage as an impartial arbiter and potential peacemaker. This is based on an absurd overestimation of the UK as some sort of soft-power saviour, valued by all parties for its impartiality in Middle Eastern affairs. Britain cannot hope to have any influence on policy if it is always last to sign up while others put their lives on the line. As so often in the past, what masquerades as tough-minded “realpolitik” is nothing of the sort. It is just another post-facto rationale for inaction.

Although it is sometimes said that Britain has yet to recover from the consequences of the invasion of Iraq, the committee report had a retro, 1990s feel. Many of the objections raised to burden-sharing in Syria were the same as those raised against humanitarian intervention in the Balkans two decades ago, when Blunt was working as special adviser to Michael Rifkind as defence and foreign secretary, and the UK was at the forefront of non-intervention. Likewise, two of the committee’s Labour members, Ann Clwyd and Mike Gapes, were veterans of the other side of that debate, and strong supporters of the Nato intervention in Kosovo in 1999. They expressed their dissent from the report’s conclusions but were voted down by their Conservative and SNP fellow committee members. “Non-intervention also has consequences,” said Gapes when he broke rank. “We should not be washing our hands and saying, ‘It’s too difficult.’”

Polling figures have shown majority public support for air strikes against IS since the spate of gruesome public executions that began last year, but nothing seems to change the calculus of the rump of anti-interventionist MPs.

All this promises an uncertain future for British foreign policy. On 6 November, the Defence Secretary, Michael Fallon, suggested that the UK’s existing position, of joining the coalition in Iraq but stopping at the borders of Syria, is “morally indefensible”. The killing of Mohammed Emwazi, aka “Jihadi John”, by a US predator drone on 12 November demonstrates what he meant. Emwazi was a Briton who was responsible for the beheading of British and American citizens, as well as countless Syrians. While the UK government was closely involved in that operation – and has previously used the justification of “self-defence” to “take out” targets in Syria – such are the restrictions placed upon it that we are forced to ask our allies to conduct potentially lethal operations (which are in our core national interests) on our behalf. The very act of “self-defence” is subcontracted out once again.

How long can this last when Islamic State poses a much greater threat to the UK than it does to the US? There is an issue of responsibility, too, with hundreds of British citizens fighting for and with Islamic State who clearly pose a grave danger to other states.


The very notion that Britain should play an expansive international role is under attack from a pincer movement from both the left and the right. There are two forms of “Little Englanderism” that have made a resurgence in recent years. On the left, this is apparent in the outgrowth of a world-view that sees no role for the military, and holds that the UK is more often than not on the wrong side in matters of international security, whether its opponent is Russia, Iran, the IRA or Islamic State. The second, and arguably just as influential, is the Little Englanderism of the right, which encompasses a rump of Tory backbenchers and Ukip. This is a form of neo-mercantilism, a foreign policy based on trade deals and the free movement of goods that regards multilateralism, international institutions and any foreign military intervention with great suspicion, as a costly distraction from the business of filling our pockets.

The time is ripe for long-term, hard-headed and unsentimental thinking about Britain’s global role. The country is not served well by the impression of British “decline” and “retreat” that has gained ground in recent times; and it is no safer for it, either. Given how quickly the security and foreign policy environment is changing, the publication of the Strategic Defence and Security Review in the coming week, alongside an update of the National Security Strategy, is likely to raise more questions than it answers. The officials responsible for its drafting do not have an easy brief, and news forecasting is a thankless task. Strategic vision and leadership must come from our elected politicians.

For all the talk of British decline, we are still one of the five wealthiest nations in the world. What we do matters, particularly at moments when our friends are under attack. However, until a new broad consensus emerges between the mainstream Labour and Conservative positions on foreign policy, the Little England coalition will continue to have the casting vote.

Syria continues to bleed profusely and the blood seeps deeper into different countries. There will be no political solution to the civil war there for the foreseeable future; to pretend that there is a hidden diplomatic solution is to wish to turn the clock back to 2011, when that might have been possible. Nor is the security situation any easier to deal with. A few hours before the attacks in Paris began, President Obama gave an interview in which he argued that he had successfully “contained” Islamic State. For the wider Middle East and Europe, that is simply not the case. Now, France will escalate its campaign, and the US will do more. Russia already has troops on the ground and will most likely send reinforcements.

The war in Syria is becoming more complicated and even more dangerous. The best that can be hoped for is that the Syrian ulcer can be cauterised. This will be achieved through the blunting of Islamic State, simultaneous pressure on Assad, and the creation of more safe places for Syrians. All roads are littered with difficulties and dangers. Yet, in the face of this ugly reality, is Britain to signal its intention to do less as every other major actor – friend and foe alike – does more? If we have a declared national interest in curtailing Islamic State and stabilising Syria – both because of the growing terrorist threat and because of the huge flow of refugees – then it is neither honourable nor viable to let others take care of it on our behalf.

John Bew is an NS contributing writer. His new book, “Realpolitik: a History”, is newly published by Oxford University Press

This article first appeared in the 19 November 2015 issue of the New Statesman, The age of terror