One thing that being a scientist has taught me is that you can never be certain about anything. You never know the truth. You can only approach it and hope to get a bit nearer to it each time. You iterate towards the truth. You don't know it.

One pound of uranium is worth about 3 million pounds worth of coal or oil.

Let's make hay while it lasts.

The entire range of living matter on Earth from whales to viruses and from oaks to algae could be regarded as constituting a single living entity capable of maintaining the Earth's atmosphere to suit its overall needs and endowed with faculties and powers far beyond those of its constituent parts.

I don't think we're yet evolved to the point where we're clever enough to handle a complex a situation as climate change. The inertia of humans is so huge that you can't really do anything meaningful.

What I tend to do is to wake about five in the morning-this happens quite often-think about the invention, and then image it in my mind in 3D, as a kind of construct. Then I do experiments with the image...sort of rotate it, and say, 'Well what'll happen if one does this?' And by the time I get up for breakfast I can usually go to the bench and make a string and sealing wax model that works straight off, because I've done most of the experiments already.

We live at a time when emotions and feelings count more than truth, and there is a vast ignorance of science