We have an obligation to help those in absolute poverty that is no less strong than our obligation to rescue a drowning child from a pond.

To explain our conventional ethical attitudes, is not to justify them.

Pro Life’ or ‘Right to Life’ movement is misnamed. Those who protest against abortion but dine regularly on the bodies of chickens, pigs and calves can hardly claim to have concern for ‘life’ as such. Their concern about embryos and fetuses suggests only a biased concern for the lives of members of our own species.

Dairy farmers routinely remove calves from their mothers at an early age so that the milk will be available for humans; anyone who has lived on a dairy farm will know that, for days after the calves have gone, their mothers keep calling for them.

We have no obligation to assist countries whose governments have policies that will undermine the effectiveness of our aid.

I argued against the view that the only obligation we have to strangers is to avoid harming them; but even if we were to take that view, the facts of climate change would demonstrate clearly that we are harming hundreds of millions, perhaps billions, of the world's poor.

What we are doing to strangers in other communities right now is, therefore, far more serious and far more widespread than the harm we would do if we were in the habit of occasionally sending out a group of warriors to rape and pillage a village or two. Yet causing imperceptible harm at a distance by the release of waste gases is a completely new form of harm, and so we lack any kind of instinctive inhibitions or emotional response against causing it. We have trouble seeing it as harm at all.

Climate change is already causing, every week, as many deaths as occurred in the terrorist attacks on September 11, 2001.

Population growth is not a reason against giving aid but a reason for reconsidering the kind of aid to give.