The Bishop of London has already underlined the timeliness of this debate and I would want to echo his commendation of the article in last week's Tablet. But I'd like also to draw your attention to another section in that same article. The 2004 World Energy Outlook of the International Energy Agency calculates that in the next 25 years, global emissions of CO2 are likely to increase by 62%, mainly from the developing world as the Chinese and the Indians rush to build coal-fired power stations to service their exploding economies.

Issues around ecology, in other words, are inseparably bound up with issues of development and economic justice. The fact is, sadly, that the pressure on the kind of development which India and China are forced into means that they are virtually unable to meet the sort of obligations we're talking about in terms of the developed countries. I hope that as we consider these environmental issues, we'll bear in mind that we can't hive them off from what the questions of what those pressures are in the world that make it, as I say, practically impossible for poorer countries to meet requirements of environmental responsibility.

What are we going to do to alter the tenor and style of development in such a way as to take away this appalling risk? A 62% increase, remember. India and China are reluctant, as some of you will have seen on the news last night, to sign up to undertakings, the Kyoto protocols, which they are unable to implement.

However (my second point) there are, as we're all aware, other countries which are well able to sign up and which refuse to do so. I hope that we shall continue to press our own government, whose leadership in this matter is, at the moment, impressive, to keep up pressure on our allies in the United States. The US is, at the moment, responsible for some 23%, I believe, of carbon emissions on the face of the globe. Unless there is a likelihood that the United States will sign up to the protocols, a great deal of what we're talking about this afternoon will be entirely academic.

Finally, again, to pick up something that the bishop has already picked up effectively, part of the Church's responsibility, we must all believe, is to hold the corner for certain issues of public and global concern that are never going to make it to the top of an electoral agenda. And that's not a cynical observation; it's simply a matter of fact that the electoral cycle encourages short-term thinking and the prioritising of certain immediate issues. The Church can afford to take a longer view. And that's not simply a pragmatic thought; the Church can afford to take a longer view because it has a particular vision of what human beings are for.

As we've heard, the frame of mind which assumes that it is right or defensible or even possible for us to approach the environment in the way in which we've increasingly been doing in the past couple of hundred years rests not on a Christian anthropology, but on a strange mythology of a divorce between human beings and their environment, a God-given right of irresponsible exploitation given to human beings, and that bears no relation to what is involved in the Christian belief that we are made in god's image and stewards of God's creation.

We can afford to take a longer perspective; we are bound to take a longer perspective, and if that longer perspective, for once, corresponds to real, perceptible urgent needs in the world around us, so much the better and so much the more urgent a task for us to undertake.

© Rowan Williams 2005