Martin Rees

The scientists who attack mainstream religion, rather than striving for peaceful coexistence with it, damage science, and also weaken the fight against fundamentalism.

Let me say that I don't see any conflict between science and religion. I go to church as many other scientists do. I share with most religious people a sense of mystery and wonder at the universe and I want to participate in religious ritual and practices because they're something that all humans can share.

It's becoming clear that in a sense the cosmos provides the only laboratory where sufficiently extreme conditions are ever achieved to test new ideas on particle physics. The energies in the Big Bang were far higher than we can ever achieve on Earth. So by looking at evidence for the Big Bang, and by studying things like neutron stars, we are in effect learning something about fundamental physics.

In the beginning there were only probabilities. The universe could only come into existence if someone observed it. It does not matter that the observers turned up several billion years later. The universe exists because we are aware of it.

Collective human actions are transforming, even ravaging, the biosphere - perhaps irreversibly - through global warming and loss of biodiversity.

It is astonishing that human brains, which evolved to cope with the everyday world, have been able to grasp the counterintuitive mysteries of the cosmos and the quantum.

The bedrock nature of space and time and the unification of cosmos and quantum are surely among science's great 'open frontiers.' These are parts of the intellectual map where we're still groping for the truth - where, in the fashion of ancient cartographers, we must still inscribe 'here be dragons.'

Indeed, our everyday world presents intellectual challenges just as daunting as those of the cosmos and the quantum, and that is where 99 per cent of scientists focus their efforts. Even the smallest insect, with its intricate structure, is far more complex than either an atom or a star.

Whether it is to reduce our carbon-dioxide emissions or to prepare for when the coal and oil run out, we have to continue to seek out new energy sources.

The scientific community should work as hard as possible to address major issues that affect our everyday lives such as climate change, infectious diseases and counterterrorism; in particular, 'clean energy' research deserves far higher priority. And science and technology are the prime routes to tackling these issues.

Indeed, the night sky is the part of our environment that's been common to all cultures throughout human history. All have gazed up at the 'vault of heaven' and interpreted it in their own way.

The most important advances, the qualitative leaps, are the least predictable. Not even the best scientists predicted the impact of nuclear physics, and everyday consumer items such as the iPhone would have seemed magic back in the 1950s.

There are strong reasons for believing that space goes on beyond the limits of our observational horizon. There are strong reasons because if you look in opposite directions, conditions are the same to within one part in 100,000. So if we are part of some finite structure then, if the gradient is so shallow, it is likely to go on much further.

It's important that everyone realizes how much scientists still don't know.

From the growth of the Internet through to the mapping of the human genome and our understanding of the human brain, the more we understand, the more there seems to be for us to explore.

In future, children won't perceive the stars as mere twinkling points of light: they'll learn that each is a 'Sun', orbited by planets fully as interesting as those in our Solar system.

We can trace things back to the earlier stages of the Big Bang, but we still don't know what banged and why it banged. That's a challenge for 21st-century science.

If you are teaching Muslim sixth formers in a school, and you tell them they can't have their God and Darwin, there is a risk they will choose their God and be lost to science.

Some global hazards are insidious. They stem from pressure on energy supplies, food, water and other natural resources. And they will be aggravated as the population rises to a projected nine billion by mid-century, and by the effects of climate change. An 'ecological shock' could irreversibly degrade our environment.

It is mistaken to claim that global problems will be solved more quickly if only researchers would abandon their quest to understand the universe and knuckle down to work on an agenda of public or political concerns. These are not 'either/or' options - indeed, there is a positive symbiosis between them.

The challenge of global warming should stimulate a whole raft of manifestly benign innovations - for conserving energy and generating it by 'clean' means (biofuels, innovative renewables, carbon sequestration, and nuclear fusion).