Not necessarily the end of the world

The biggest existential threat to humans is now humanity

This article is taken from the November 2022 issue of The Critic. To get the full magazine why not subscribe? Right now we’re offering five issues for just £10.

Martin Rees gets briskly to the point on page two: “The Earth has existed for 45 million centuries, but this is the first century in which one dominant species can determine, for good or ill, the future of the entire biosphere.” That’s an alarming sentence: first, 45 million centuries is more vertiginous than the usual 4.5 billion years; even more vertiginous is the terrible truth that all life now suddenly depends on the sanity or otherwise of humanity. Would that we were all Martin Rees.

Rees, Astronomer Royal, former Master of Trinity, Cambridge, and President of the Royal Society, is certainly an establishment figure but, unusually for such folk, he is eminently sane. If Science is to Save Us, like his previous books and articles, is a balanced and careful assessment of evidence and possible outcomes. 

If Science is to Save Us, Martin Rees (Polity, £20)

The big, terrifying outcome in this case is human extinction, but Rees calms our nerves at the end of the book with his list of sane people. Pope Francis, David Attenborough, Bill Gates and Greta Thunberg are, he writes: “individuals who resonate with science, but can inspire the ethical guidance and motivation that science alone can’t offer”.

The heart of the matter is that the biggest existential threat to humans is now humanity. The dinosaurs knew nothing of the asteroid that wiped them out 60 million years ago. We will know everything if we are ever terminated by climate change, nuclear war, hyper-intelligent machines or bad biotech actors who are now capable, in the foetid privacy of their bedrooms, of brewing up the next, and last, pandemic. We will know because we created them all.

Rees summarises and assesses the challenges in his first chapter. Correctly, I think, he says it is “highly likely” that atmospheric carbon dioxide will still be rising in 2050. Public resistance to the changes required will get in the way, just as the anti-vaxxers got in the way of resistance to the pandemic. Of course, anti-vaxxers are nutters, but it won’t be just nutters resisting the sort of sacrifices needed to cool the planet. So, as 2050 looms, we will be choosing Plan B: CO2 extraction from the atmosphere or vast and incredibly risky geo-engineering projects. 

Dealing with biotech is even more complex, basically because we don’t really know what we are doing. What kind of people will emerge from genetically lengthened or enhanced lives? Artificial Intelligence, meanwhile, is now a gold rush that cannot be stopped. Rees points out that when Google’s parent company Alphabet took over the British AI company DeepMind, the latter’s ethical committee was disbanded. Geeks, I’m afraid, cannot be trusted. 

History tells us that individual civilisations rise and fall but what we now know, or should know, is that we have through population growth and technology created a single global civilisation. We should have learned from Covid that when the bell tolls it tolls for us all. “Indeed,” Rees writes, “we have zero grounds for confidence that human civilisation — or even humanity itself — can survive the worst that future technologies could bring.”

The Royal Society should be secular but not anti-religious

The remaining chapters try to answer Tolstoy’s question, “What, then, must we do? One answer, which many have suggested, is to get off this risk-laden planet. Rees dismisses this: mass migration from Earth is a “delusion and a dangerous one”. His solutions are more intricate and interesting than that.

Broadly speaking, as the title suggests, the solution is scientific. But Rees is no believer in scientism, the idea that science is the only route to all the truth of the world, especially when it is reinforced by the cult of the New Atheism championed by the likes of Sam Harris and Richard Dawkins. Some of the NAs — “small-time Bertrand Russells”, he calls them — stirred up trouble at the Royal Society. 

He responded that the RS should be secular but not anti-religious and, as evidence, he supplies a beautiful quote from Darwin, the greatest hero of the NAs, on atheism: “The whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope and believe as he can.” Amen to that.

This is typical of the form of Rees’s thought. It is not, for him, the job of science to be ideologically driven. Instead, it should be led by people with open minds and good intentions. 

One of his heroes in this context is Joseph Rotblat, a physicist who worked on the Manhattan Project. He did so because he believed in the possibility that Hitler would acquire an atom bomb first. When he no longer believed this, he became the only scientist to leave the project. He then went on to establish the Pugwash conferences, which kept the West and the Soviets talking to each other during the Cold War. He also wanted to create a Hippocratic-style oath for scientists; they would swear to do no harm.

All our primary threats will be global in impact

At a less elevated level we also need to get the money right. The UK Treasury evaluates long-term projects using a discount rate of 3.5 per cent until 2050. This is reasonable for an office block, completely ridiculous if you are spending to avoid the destruction of humanity.

Politics is, as it always is, the great stumbling block. A disaffected electorate counting the cost of global warming will create a disaffected political class. Equally, a Chinese or Russian style autocracy has a tendency to create bad science (neither of their Covid vaccines were much good) or keep good science to themselves. If the latter happens, there is no hope because, see above, all our primary threats will be global in impact.

“We need,” writes Rees, “to think globally, we need to think rationally, and we need to think long term.”

One of the most attractive attributes of this book is Rees’s instinct for fairness. I first noticed the intensity and clarity of this when he explained to me what is wrong with our honours system. It is class-biassed and, for all their flummery, it is not the high honours that have the most impact, but the lowlier ones. 

Here, fairness emerges in odd little asides. Each Nobel Prize, for example, can only have a maximum of three recipients. But contemporary science is almost always a collective effort. The astronomical detection of gravitational waves was made by 70 observatories worldwide and the resulting published paper had 1,000 authors. Rees observes that information technology has “democratised science”; this makes a nonsense of the restriction to three recipients.

The book ends with a quote from Margaret Mead: “Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it’s the only thing that ever has.” That is Rees’s faith in a nutshell or perhaps it is just his hope. Either way this book is both pleasurable and essential — a guide to the worst that can happen by one of our best.

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