The cell is a city of production centres, each part working away like mad, and it's co-ordinated. Six trillion cells in a body - you can't help but be moved.

Pluripotent cells have the ability to grow into any cell in the body.

Like our attitude to love, truth and goodness, we seem to be confident about knowing what beauty is - certain, even dogmatic - until we think hard about the idea, whereupon all confidence flies away.

If you look at any leaf on any tree branch, it's similar to but not exactly a repetition of the previous branch. So the new science of complexity or showing how an architecture can be produced just as quickly, cheaply and efficiently by using computer production methods to get the slight variation, the self-similarity.

I was working with stem cells as part of a NASA programme. We realised that the science of stem-cell proliferation was also fundamental to cancer cells when cancer enters the phase of metastasis.

You have to believe in a placebo or it won't work, but if it works, it's obviously working in some indirect way, through feedback in the immune system, let us say, or in the willpower of the patient to take a more strenuous exercise in their own therapy.