We have an overdraft with the earth something in excess of 130 per cent. We currently consume something like 30 per cent over and above what we are replacing and rather like an overdraft at a bank that can't go on.

I think that will only really change when the human races begins to suffer some of the extremely severe consequences of climate change which may be some decades ahead. They will then realise, as we have with the financial crisis, that we are up against the wall and hitting the buffers and we have got to change.