Earth has been around for about 45 million centuries but, according to astrophysicist and author Sir Martin Rees, the century we’re living in is different in a crucial way. For the first time, a single species – our own – carries the future of the planet in its hands. The choices we make in the next few decades could lead to dramatically different outcomes for our descendants and the rest of life on Earth.

Sir Martin is Britain’s astronomer royal, former director of the Institute of Astronomy at the University of Cambridge and an expert in phenomena related to the origin and evolution of the universe. In his latest book, On the Future, he considers a more immediate matter: the potential of science and technology to make the world a better place – or a more dangerous one. He spoke to The Globe and Mail ahead of his public talks this week at the University of Toronto and the Perimeter Institute in Waterloo, Ont.

What concerns you when you consider the future course of this century?

There are two types of threats. One is the threat that we are imposing collectively because the world’s population is higher than ever and we are, each of us, more demanding of energy and resources and possibly pushing the planetary environment and climate over tipping points. A second is that we are in a situation when individuals are so empowered by technology that even a few people can have an effect that could cascade globally. So I think we are vulnerable.

If today’s challenges are unique, what needs to be different about our response?

At the political level, there’s probably a need for more international organizations to cope with new challenges related to energy, climate, monitoring the web and so on. Of course, the problem is to motivate politicians to use some of their goodwill and capital to make hard trade-offs on issues which are long term and where the main beneficiaries may be people who live decades in the future and in distant parts of the world.

As a student in the 1960s, you participated in demonstrations for nuclear disarmament, just as students today are demanding action on climate change. Do you think this kind of activism makes a difference?

Public campaigning is very important because politicians care about what’s in their inbox and what’s in the press. They will do the right thing if they don’t fear losing votes by so doing. The climate campaigns, I think, can make a difference because they can help change attitudes – for example, by making waste less acceptable.

Does it worry you when politicians appear to gain traction by retreating from global thinking?

It does, and that’s why I’m pessimistic that international actions along the lines of the Paris climate agreement are really doing enough. I think the answer is to enhance the rate of research and development into more forms of clean energy. For example, we need to make renewable energy cheap enough to allow people in the developing world to leapfrog directly to it instead of to coal, just as they’ve leapfrogged to mobile phones. What happens in this century depends on our wisely applying technology, but also on our decisions being informed by a set a values which science by itself can’t provide.

Do you think we need a common value system in order for humanity to survive?

I think we need peaceful co-existence between different value systems. But one would hope that with a greater awareness of other parts of the world, there will be certain common attributes of all value systems that can help us relate as human beings.

Why should people pay attention to science?

Science is part of our culture and it’s the one truly global culture which straddles all boundaries of nationality and faith. But also, so many of the decisions that have to be made have a scientific element, whether it’s in the area of health, climate, energy … all these things. In order for citizens to be able to vote responsibly, they have to have an awareness of science, and enough of a feeling for numbers not to be bamboozled.

How does being an astronomer affect your thinking on the future?

There’s one perspective astronomers have which others may not, and that is an awareness of a long future. Most educated people know that we’re the outcome of about four billion years of evolution, from the first primordial life to the biosphere of which we’re a part. But I think many people nonetheless think that in some sense we’re the culmination of it all. Astronomers know that the sun is less than halfway through its life. And so we realize that humans are maybe at a halfway stage, and that any creatures witnessing the sun’s demise will be as different from us as we are from slime mould.

The Globe and Mail, September 29, 2019