The European: Let’s talk about the end of life on earth. Some scientists argue that all life runs through an arc in which a time of flourishing is inevitably succeeded by sudden decline. Do you agree?
Rees: On a local perspective there are clearly ups and downs. However, astronomers have a special perspective on the far future, for reasons I can explain quickly. The stupendous timespans of the evolutionary past are now part of common culture – except, maybe, in the US Bible Belt, and in parts of the Islamic world. But most people still somehow think that humans are the culmination of the evolutionary tree. That hardly seems credible to astronomers. Our Sun formed 4.5 billion years ago, but it’s got 6 billion more before the fuel runs out. It then flares up, engulfing the inner planets. And the expanding universe will continue – perhaps forever – destined to become ever colder, ever emptier. To quote Woody Allen, eternity is very long, especially towards the end. Post-human evolution – here on Earth and far beyond – could be as prolonged as the Darwinian evolution that’s led to us – and even more wonderful. And of course evolution is even faster now than it was when it was governed by natural selection – intelligent species can use genetic technology, and perhaps machines will take over.
The European: Do you think that the end of human civilization will come from natural or anthropogenic causes?
Rees: Over most of history, threats to humanity have come from nature – disease, earthquakes, floods, and so forth. But this century is special. It’s the first where one species – ours – has Earth’s future in its hands, and could jeopardize life’s immense potential. We’ve entered a geological era called the anthropocene. The anthropocene began with the advent of thermonuclear weapons. The threat of global nuclear annihilation involving tens of thousands of bombs has been in abeyance since the Cold War ended. But later in the century, a global political realignment leading to a standoff between new superpowers, that could be handled less well or less luckily than the Cuba crisis was. But devastation could arise insidiously rather than suddenly, through unsustainable pressure on energy supplies, food, water, and other natural resources. Indeed these pressures are the prime ‘threats without enemies’ that confront us. And they’ll become ever more intractable as the population rises.
The European: Which catastrophe do you see as most likely to bring about humanity’s extinction?
Rees: I don’t think it’s likely that any catastrophe will wipe us all out. But I think humanity will have a bumpy ride throughout the 21st century. In addition to the pressures on the environment I’ve just mentioned, there are others which I describe in my recent book ‘From Here to Infinity – Scientific Horizons.’ But there’s a downside: the same technologies that promise so much also open up new vulnerabilities. For instance, global society depends on elaborate networks – electricity grids, air traffic control, international finance, just-in-time delivery and so forth. Unless these are highly resilient, their manifest benefits could be outweighed by catastrophic (albeit rare) breakdowns cascading through the system. And the threat is terror as well as error; concern about cyber-attack, by criminals or by hostile nations, is rising sharply. And there are such concerns , too, in the ‘bio’ area. Advances in genetics offer huge potential for medicine and agriculture. But already the genomes for some viruses – polio, Spanish Flu, and SARS — have been synthesized. Expertise in such techniques will become widespread, posing a manifest risk of ‘bioerror’ or ‘bioterror.’
The European: And we cannot trust science to control those dangers and to proceed with due respect of the dangers implicit in that kind of research?
Rees: We’re kidding ourselves if we think that those with technical expertise will all be balanced and cautious: expertise can be allied with fanaticism – not just the traditional fundamentalism that we’re so mindful of today, but that exemplified by some ‘new age’ cults, extreme eco-freaks, violent animal rights campaigners and the like. And there will be individuals with the mindset of those who now unleash computer viruses. The global village will have its village idiots – and their idiocies can have global range. The huge empowerment of individuals or small groups by fast-developing technologies presents novel hazards – and will heighten the tension between security, privacy, and freedom. Incidentally, there’s a mismatch between public perception of very different risks and their actual seriousness. We fret unduly about carcinogens in food and low level radiation. But we are in denial about ‘high-consequence’ events, natural or man-made, that may be improbable, but where even one occurrence could be too many.
The European: You once estimated the odds for a global catastrophic event during the 21st century at 50 percent. So we’re as likely to survive this century as we are to become extinct?
Rees: I never made this claim about human extinction, which I think is unlikely, however pessimistic we are. However, in a book written some years ago entitled ‘Our Final Century’ – or ‘Our Final Hour’ in the American edition – I thought there was a 50-50 chance of some event that would be as great a setback to civilization as a global nuclear war. It could indeed be such a war, but it could also be triggered as a consequence of some new 21st century technology.
The European: What is easier for humans to tackle: singular events or long processes of decline or destruction?
Rees: Neither is easy. But the main problem is that, all too often, the parochial and the immediate trump global and the long-term. Politicians look to their own voters – and the next election. Stockholders expect a pay-off in the short run. Medical research focuses on diseases of the rich — not enough on tropical diseases. There’s a current slogan in Britain, promulgated unconvincingly by our Conservative leaders, that ’We’re all in this together.’ But we need to realize, even more compellingly, that we’re all on this crowded world together. Problems caused by shortage of food, water, resources – and the transition to sustainable low carbon energy – can’t be solved by each nation separately. Can our sympathies become more broadly international? And can our institutions prioritize projects that are long-term in a political perspectives, even if a mere instant in the history of our planet ? Many of today’s young people will live into the 22nd century. — and what we’re doing to the climate will resonate many centuries beyond that.
The European: Do we need a world government to rein in global risks?
Rees: The challenges I’ve mentioned almost all need to be tackled at an international level — even a global level. It could be that we need new institutions – for instance an international body analogous to the WHO or the IAEA to deal broadly with all energy issues. Another question, of course, is whether the role of individual national governments will be eroded by, on the one hand, the greater power of multinational corporations, and on the other, the growing ability of social media to trigger mass movements or shifts in opinion that transcend national boundaries.
The European: An optimist might say: “The history of technology is such that the benefits have mostly outweighed the dangers. We are increasingly well positioned to control our destiny.” Is that an optimism you share?
Rees: Up till now, the benefits have indeed outweighed the dangers. For most people in the world, there has never been a better era in which to live. We can truly be techno-optimists. The innovations that will drive economic advance – information technology, biotech and nanotech – can boost the developing as well as the developed world. Creativity in science and the arts is open to hugely more than in the past. And modern engineering and agriculture could provide food and energy for 9 billion by mid-century. That’s all good news. But as technologies grow more powerful, and the world gets more interconnected, the stakes are higher. What is most depressing is the widening gap between what the world is actually like and what it could be like. For instance, if the political will were there, the lot of the world’s ‘bottom billion’ could be substantially improved, without significant detriment to the rest of us – indeed it would reduce the causes of embitterment and therefore make us all more secure. The fact that this manifestly ethical and immediate goal hasn’t been achieved makes me pessimistic about concerted and effective action to guard against long-term issues of environment, energy, resources and climate.
The European: Skeptics point out that new technologies often have unintended consequences. How can we reason about, or try to address, something that will only happen in the future?
Rees: The technologies that already exist have huge future potential, But, as you imply, there is the possibility of new ones. We can’t predict the nature of these, let alone their social consequences. Indeed, scientific forecasters have a dismal record. One of my predecessors as Astronomer Royal said space travel was “utter bilge”. Few in the mid-20th century envisaged the transformative impact of the silicon chip or the double helix. The iPhone would have seemed magical even 20 years ago. So, looking 50 years ahead we must keep our minds open, or at least ajar, to what may now seem science fiction. Let me highlight two areas. Human nature and human character have changed little for millennia. Before long, however, new cognition-enhancing drugs, genetics, and ‘cyborg’ techniques may alter human beings themselves. That’s something qualitatively new – and disquieting because it could portend more fundamental forms of inequality if these options were open only to a privileged few. And robotics is advancing apace – though the capabilities of robots are still uneven. Even back in the 1990s IBM’s ‘Deep Blue’ beat Kasparov, the world chess champion. But robots can’t yet recognize and move the pieces on a real chessboard as adeptly as a child can. Later this century, however, their more advanced successors may relate to their surroundings (and to people) as adeptly as we do. Moral questions then arise. We accept an obligation to ensure that other human beings, and indeed some animal species, can fulfill their ‘natural potential. So what’s our obligation towards sophisticated robots? Should we feel guilty about exploiting them? Should we fret if they are underemployed, frustrated, or bored?
The European: What progress is good progress?
Rees: The problems I’ve just mention are matters for the conjectural future. As science empowers us more, there’ll be a widening gulf between what it enables us to do, and what it’s prudent or ethical actually to do. But already, possible applications of science confront us with hard choices. To take a few at random: Who should access the ‘readout’ of our personal genetic code? Should we build nuclear power stations – or wind farms – to keep the lights on? Should we plant GM crops? Should the law allow ‘designer babies’? Such questions aren’t purely scientific: they all involve ethics, economics and social policies as well. In domains beyond their special expertise, scientists have no enhanced authority and will have a wide range of political and social perspectives. But as “scientific citizens” they have a special obligation to engage. They shouldn’t be indifferent to the fruits of their ideas. They should try to foster benign spin-offs – commercial or otherwise. Scientists should resist dubious or threatening applications of their work, and alert the public and politicians to perceived dangers.
The European: You’re an advocate of space exploration and colonization. But presumably, we’d take some of our most dangerous technologies along with us. So what’s the value of seeking survival outside of Earth?
Rees: We depend on space technology for communication, environmental monitoring, satellite nativation, and so forth – and also for a lot of important science. But this doesn’t involve sending people. Indeed, the practical case for sending people gets ever-weaker with each advance in robots and miniaturization — indeed as a scientist or practical man I see little purpose in manned spaceflight at all. But as a human being, I’m an enthusiast — I hope some people now living will walk on Mars, simply as an adventure. They may be Chinese – China has the resources, the dirigisme government, and maybe the willingness to undertake an Apollo-style program that leapfrogs what the Americans did. But if others boldly go to the Moon and beyond, it’s more likely to be via cut-price ventures, spearheaded by individuals prepared to accept high risks – perhaps even ‘one way tickets’ – driven by the same motives as early explorers, mountaineers, and the like. That’s why I’m hugely enthusiastic about the new private space companies fronted by entrepreneurs with resources, and high-tech expertise. And, by the way, I think the phrase ‘space tourism’ should be avoided. It lulls people into believing that such ventures are routine and low-risk. And if that’s the perception, the inevitable accidents will be as traumatic as those of the Space Shuttle were. Instead, these cut-price ventures must be ‘sold’ as dangerous sports, or intrepid exploration.
The European: In other words, space will always remain a frontier to the human species?
Rees: Don’t ever expect mass emigration. Nowhere in our Solar system offers an environment even as clement as the Antarctic or the top of Everest. Space doesn’t offer an escape from Earth’s problems. A century or two from now, there may be small groups of pioneers living independent from the Earth – on Mars or on asteroids. Whatever ethical constraints we impose here on the ground, we should surely wish such pioneers good luck in genetically modifying their progeny to adapt to alien environments – a step towards divergence into a new species. The post-human era would then begin.
The European: Stories about the apocalypse are woven into the cultural fabric of many civilizations, and we generally regard them as irrational and unfounded. Is there a rational argument to be made for taking these stories seriously – for example, because they provide an impetus for cooperation and conservation?
Rees: We are all embedded in our culture (and of course science is the one truly global culture). And of course myths developed because of the human craving to find meaning and comfort in the lives. But now, unlike our forebears, we know a great deal about our world – and indeed about what lies beyond. Many phenomena still make us fearful, but the advance of science spares us from irrational dread. We know that we are stewards of a precious ‘pale blue dot’ in a vast cosmos – a planet with a future measured in billions of years – whose fate depends on humanity’s collective actions this century. But all too often the focus is short term and parochial. We downplay what’s happening even now in impoverished far-off countries. And we give too little thought to leaving a fair inheritance for our grandchildren. We need to broaden our sympathies in both space and time, and perceive ourselves as part of a long heritage and stewards for an immense future. And to be guided by the best science, but also by values that science itself can never provide.
Interested in global risks and risk management? Read our interview with Nick Bostrom, director of the Future of Humanity Institute at Oxford.