We seem gradually to be groping toward an understanding of the world of subatomic particles, but we really do not know how far we have yet to go in this task.

The philosophical question before us is, when we make an observation of our track in the past, does the result of our observation become real in the same sense that the final state would be defined if an outside observer were to make the observation?

If we have an atom that is in an excited state and so is going to emit a photon, we cannot say when it will emit the photon. It has a certain amplitude to emit the photon at any time, and we can predict only a probability for emission; we cannot predict the future exactly.

In talking about the impact of ideas in one field on ideas in another field, one is always apt to make a fool of oneself.

It makes sense to invest in new work. It's almost like having a research department in a scientific laboratory. You have to try things out. You'll make some bad mistakes. Some things will fail but at least you'll energise the organisation.

Relativity must replace absolutism in the realm of morals as well as in the spheres of physics and biology.

I'm not actually that bothered about the 'science fiction-ness' of 'Doctor Who.'

Science is performed by people, and it's subject to all the various foibles that plague the rest of our social dynamics.