If all of this, all the life of a stream of water, can be nothing but a pile of atoms, how much more is possible?

Ordinarily it would take me about fifteen minutes to get a hallucination going," wrote Feynman, "but on a few occasions, when I smoked some marijuana beforehand, it came very quickly.

I am going to tell you what nature behaves like. If you will simply admit that maybe she does behave like this, you will find her a delightful, entrancing thing. Do not keep saying to yourself, if you can possibly avoid it, 'But how can it be like that?' ...Nobody knows how it can be like that.

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.

It appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management.

I love to think. I once considered taking drugs as an attempt to better understand an altered state of mind; however, I decided not to. I didn't want to chance ruining the machine.

We have a habit in writing articles published in scientific journals to make the work as finished as possible, to cover up all the tracks, to not worry about the blind alleys or describe how you had the wrong idea first, and so on. So there isn't any place to publish, in a dignified manner, what you actually did in order to get to do the work, although, there has been in these days, some interest in this kind of thing.