As if eerily timed to coincide with the alarming report earlier this week by the Intergovernmental Panel on Climate Change, Lord Martin Rees manages weighty, often scary, matters with an eminently accessible lightness of touch in On the Future: Prospects for Humanity. Rees is a trusted veteran and inveterate prognosticator. Among his many roles, he has been president of Britain’s community of top scientists, The Royal Society, and member of the US National Academy of Sciences. He is also co-founder of the Centre for the Study of Existential Risk — a research group that ponders potential global calamities. His publications include many reports on the future of the environment and his Final Century (in the US Final Hour), published 15 years ago, in which he calculated that society as we know it has no more than a 50-50 chance of surviving the 21st century. Given the latest findings he is not about to renege on those queasy odds.
In this short, crisply written new book, Rees employs a mix of approaches, from tipping-point projections based on soundly based past and current trends, to evaluations of outlandish post-human futurology, involving selves downloaded into immortal software to travel beyond the galaxy. He steers a critical middle course between enthusiasm and scepticism, utopian dreams and dystopian nightmares, cheerful optimism amid counsels of gloom. He ponders the future of science and technology, and signals the importance of values for survival, including religion.
Rees has a checklist of take-home messages from the perspective of the “Anthropocene” — the study of the origins of human impact on the Earth’s ecosystems, culminating in the current era of rapid climate change heading for disaster. The hazards “are those that humans themselves engender,” he writes. “These now loom far larger, and they are becoming more probable, and potentially more catastrophic, with each decade that passes.”
Ringing a death knell — through nuclear weapons proliferation, global warming, dangerous and dirty energy sources, natural pandemics, species extinction, scientific giant collider experiments that could tear a hole in space (a prospect, by the way, he believes unlikely, along with imminent meteor cataclysms) — Rees cites two kinds of overall threat. There are those “that we’re causing collectively to the biosphere, and threats that stem from the greater vulnerability of our interconnected world to error or terror induced by individuals or small groups.” He is referring principally to global warming, and bio-terrorism. One way or another it is down to human beings.
Rees reflects persistently on the uniqueness of our planet, its species and ecosystems, over which we have a duty of care as “stewards in an especially crucial era.” His aim is not just to scare the wits out of us, but to encourage us to act — to influence public opinion in the hope of deflecting identifiable trajectories towards foreseeable disasters. Corporate and governmental short-termism and self-interest are the enemies of the planet, he declares, and so is a “public [which is] still in denial”.
When it comes to the next three decades Rees focuses on the population clock, which he believes is under-discussed because the arguments are tainted with suspicions of eugenics. He predicts a world population of 9bn by 2050, and perhaps a decade or so earlier. Demographics in Africa, he argues, could even push us towards 11bn beyond 2050.
But how will food security keep pace? Water and energy supplies, greedily consumed and squandered by western eating habits, are destined to approach tipping points before the half-century. He cites 1,500 litres of water to grow 1kg of wheat; but 10 times as much water, and 20 times as much energy, to provide a kilogramme of beef.
By 2050 half the world’s children will live in Africa, and the poorest “the bottom billion”. Their predicament is invidious. They have mobile phones, social media, but no proper toilets and clean water. So “ . . . these same technologies mean that those in deprived parts of the world are aware of what they are missing”, triggering “greater embitterment, motivating mass migration or conflict”.
The answer, he is convinced, lies not only in agricultural technology, meat substitutes, modification of the rice genome to increase production, and other GM strategies, but a change of lifestyles for all of us. How about us becoming vegans, he suggests. “The trouble is,” he concedes, “long-term goals tend to slip down the political agenda.”
Rees puts major emphasis on the future of artificial intelligence. AI makes the news with stories about self-driving cars, recognition technology and the threats to employment. But he focuses on the future of self-learning machines designed to solve highly complex problems — which in time could include environmental, economic and societal decisions. In particular, he traces the career of Demis Hassabis, the north London wunderkind who “studied the nature of episodic memory and how to simulate groups of human brain cells in neural net machines”.
This mimicking of the human brain was the basis of Hassabis’s AI start-up research company, DeepMind, sold to Google in 2014 for $600m. Hassabis’s work led to the development of AlphaGo, a machine that in 2016 beat the world champion at Go, the most complex board game ever devised, demanding high levels of intelligence and intuition. AlphaGo had been fed with huge numbers of games and played itself. The key to its success was not just memory, but the capacity to envisage future events, or moves, and their consequences at prodigious speeds and quantities of data. Hassabis was to call this function “machine imagination”. The future of self-learning systems, scaled up and applied to problem-solving in the real world, will lead, Rees warns, to the delegation, and ultimately takeover, of crucial decision-making to machines. Machine decisions could be extended to health, environment, security, the economy and criminal justice, reducing human responsibility on a wide scale.
In a chapter titled “The Limits and Future of Science”, no small topic for a slim volume, it is surprising to read a scientist, whose discipline is heavily based on physics and mathematics, declaring that “reductionism isn’t conceptually useful”. Ten years on from the New Atheism campaign of ultra-reductionists Richard Dawkins et al, Rees, while stating he is an atheist, declares that he shares a sense of “mystery” with those who believe in God. Science is not an arbiter of values, he insists, and the bigger questions of existence lie within the provinces of philosophy and theology.
Facing joint uncertain futures, Rees advocates alliances between science and religious faiths. He is a member of the Pontifical Academy of Sciences at the Vatican, he tells us, where he participated in a conference in 2014 on sustainability and climate that led to the “timely scientific impetus” of Pope Francis’s encyclical on the environment, “Laudato Si”. He singles out the Catholic Church from among other denominations and religions for its “durability” and “long-term vision”, its “focus on the world’s poor”.
While crediting technology with creating a more “positive” world, Rees raises more questions than he settles when it comes to relief of poverty. The issue was exposed and hotly contested, as it happened, by that encyclical. Francis opts for wealth distribution, as opposed to wealth creation in the global economy — the latter of which economists (including Catholic ones) claim has brought a billion people out of poverty in recent decades.
Rees might have taken issue, moreover, with the Catholic Church on population and HIV-Aids. After all, papal doctrine has continued to denounce birth control and safe sex, despite the fact that Sub-Saharan Africa accounts for an estimated 69 per cent of people living with HIV in 2011, and 70 per cent of all Aids deaths: 1.2m people. Rees is also discreet on the far-reaching influence of President Trump’s exit from international climate treaties, the dismantling of the US Environmental Protection Agency, and declarations that global warming is a hoax invented by the Chinese to undermine US manufacturing.
Rees’s political vision calls for a degree of national surrender to new global organisations that will regulate technological innovation. On ethics, he urges scientists to accept moral responsibility for the uses to which their innovations might be put. It is 20 years since the eminent British cell biologist Professor Lewis Wolpert argued for the morally neutral status of science in his notable Medawar Lecture. Rees is adamant that there is no ivory tower sufficiently high and remote for scientists to disclaim accountability for the uses to which their researches are put.
In this terse, passionate, visionary late warning, Rees sees our planet as “Space-Ship Earth” hurtling through the void, “its passengers anxious and fractious”. He views the present as a pressing opportunity for planning, horizon-scanning, and awareness of long-term risks. And he acknowledges that technology has done much to bring us to this point of future peril, as well as offering us the means to escape those dangers. Yet he rightly concedes in his final sentence that our choices must be guided by values that science and technology cannot provide. Quite what those values might be, other than acknowledgment that life and the planet are unique and special, would require another, rather different, book.
On the Future: Prospects for Humanity, by Martin Rees, Princeton University Press, RRP£14.99/$18.95, 272 pages
John Cornwell is director of the Science & Human Dimension Project at Jesus College, Cambridge