Although it is uncertain, it is necessary to make science useful. Science is only useful if it tells you about some experiment that has not been done; it is not good if it only tells you what just went on.

The world is a dynamic mess of jiggling things

It is in the admission of ignorance and the admission of uncertainty that there is a hope for the continuous motion of human beings in some direction that doesn't get confined, permanently blocked, as it has so many times before in various periods in the history of man.

What we need is imagination, but imagination in a terrible strait-jacket.

All the time you're saying to yourself, 'I could do that, but I won't,'--which is just another way of saying that you can't.

I think it's much more interesting to live not knowing than to have answers which might be wrong.

One does not, by knowing all the physical laws as we know them today, immediately obtain an understanding of anything much. I love only nature, and I hate mathematicians.