It was about three o'clock at night when the final result of the calculation [which gave birth to quantum mechanics] lay before me ... At first I was deeply shaken ... I was so excited that I could not think of sleep. So I left the house ... and awaited the sunrise on top of a rock.

Imagine a survivor of a failed civilization with only a tattered book on aromatherapy for guidance in arresting a cholera epidemic. Yet, such a book would more likely be found amid the debris than a comprehensible medical text.

What I like about sceptics is that in good science you need critics that make you think: 'Crumbs, have I made a mistake here?' If you don't have that continuously, you really are up the creek. The good sceptics have done a good service, but some of the mad ones I think have not done anyone any favours.

I am a futurist, projecting trends in science into the next decades and century, but ironically my two daughters - one is a neuroscientist and the other is a pastry chef - tell me that my taste in music is positively prehistoric.

We used to think that you could pay attention to five to nine things at a time. We now know that's not true. That's a crazy overestimate. The conscious mind can attend to about three things at once. Trying to juggle any more than that, and you're going to lose some brainpower.

[Marijuana] doesn't have a high potential for abuse, and there are very legitimate medical applications. In fact, sometimes marijuana is the only thing that works... [I]t is irresponsible not to provide the best care we can as a medical community, care that could involve marijuana. We have been terribly and systematically misled for nearly 70 years in the United States, and I apologize for my own role in that.