The carbon dioxide concentration in the atmosphere is measured. It's uncontroversial. It's going up. We know that has a tendency to warm the atmosphere and we should be worried about that.

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

In our interconnected world, novel technology could empower just one fanatic, or some weirdo with a mindset of those who now design computer viruses, to trigger some kind of disaster. Indeed, catastrophe could arise simply from technical misadventure - error rather than terror.

The important point there is that when people talk about a mean temperature rise of say two, three or four degrees that's a sort of global average which really is a signature of large scale change in climatic patterns.

I'm not a specialist in the science but I have followed it fairly closely and it seems to me that there is among the experts a clear consensus that potential climate change is something to worry about.

I would support peaceful co-existence between religion and science because they concern different domains. Anyone who takes theology seriously knows that it's not a matter of using it to explain things that scientists are mystified by.

I suspect there could be life and intelligence out there in forms that we can't conceive. And there could, of course, be forms of intelligence beyond human capacity-beyond as much as we are beyond a chimpanzee.