Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.

At no period of [Michael Faraday's] unmatched career was he interested in utility. He was absorbed in disentangling the riddles of the universe, at first chemical riddles, in later periods, physical riddles. As far as he cared, the question of utility was never raised. Any suspicion of utility would have restricted his restless curiosity. In the end, utility resulted, but it was never a criterion to which his ceaseless experimentation could be subjected.

I don't know much about climate change. But I'm pretty sure we better figure out what to do to lessen its impact - at least its health impact - and that's not going to happen unless you have a lot of young talent interested in these topics.

I think of the brain as a computational device: It has a bunch of little components that perform calculations on some small aspect of the problem, and another part of the brain has to stitch it all together, like a tapestry or a quilt.

The recurrence of a phenomenon like Edison is not very likely. The profound change of conditions and the ever increasing necessity of theoretical training would seem to make it impossible. He will occupy a unique and exalted position in the history of his native land, which might well be proud of his great genius and undying achievements in the interest of humanity.

Faced with the evidence, many deniers have started to admit that global warming is real, but argue that humans have little or nothing to do with it.