"What delighted me was that it's 30 years from now — not next week or next year. … That would be totally hopeless; that would be terrifying, in fact. Time is on our side in this one — that's why it's such a wonderful illustration of the process... I say 30 years is a good long time to do something about it if it is a problem … We should be thankful we have this kind of notice."

"We have to beef up our searches, which are now pretty dismal, so we can find out about these things before we get hit. … It takes a dramatic event to get people's attention, and we thought the comet crash with Jupiter might have done the job. … we tend to ignore an extraterrestrial hazard that could reduce the planet to rubble. … What we really need is a good scare."

"Our own tung should be written cleane and pure, vnmixt and vnmangled with borrowing of other tunges."

"...the 'size' of science has doubled steadily every 15 years. In a century this means a factor of 100. For every single scientific paper or for every single scientist in 1670, there were 100 in 1770, 10,000 in 1870 and 1,000,000 in 1970."

"Even in physics, there is no infallible procedure for generating reliable knowledge. The calm order and perfection of well-established theories, accredited by innumerable items of evidence from a thousand different hands, eyes and brains, is not characteristic of the front-line of research, where controversy, conjecture, contradiction and confusion are rife. The physics of undergraduate text-books is 90% true; the contents of the primary research journals of physics is 90% false. The scientific system is as much involved in distilling the former out of the latter as it is in creating and transferring more and more bits of data and items of 'information'."

"Ethics is not just an abstract intellectual discipline. It is about the conflicts that arise in trying to meet real human needs and values."

"The communication of modern science to the ordinary citizen, necessary, important, desirable as it is, cannot be considered an easy task. The prime obstacle is lack of education. … There is also the difficulty of making scientific discoveries interesting and exciting without completely degrading them intellectually. … It is a weakness of modern science that the scientist shrinks from this sort of publicity, and thus gives an impression of arrogant mystagoguery."

"A new scientific theory is seldom stated with such clarity by its original author, and usually takes many years to creep into public conciousness."

"Art imitates Nature, and Necessity is the Mother of Invention."

"Envy […], like a cold poison, […] benumbs and stupefies. And thus conscious as it were of its own impotence, it folds its arms in despair, and sits cursing in a corner."

"By reading a man does as it were antedate his life, and makes himself contemporary with the ages past. And this way of running up beyond one's nativity is much better than Plato's pre-existence, because here a man knows something of the state, and is the wiser for it, which he is not in the other."

"A man may as well expect to grow stronger by always eating, as wiser by always reading. Too much over-charges nature, and turns more into disease than nourishment. 'Tis thought and digestion which makes books serviceable, and gives health and vigour to the mind."

"A brave mind is always impregnable. True courage is the result of reasoning."

"Knowledge is the consequence of time, and multitude of days are fittest to teach wisdom."

"To believe a business impossible is the way to make it so. How many feasible projects have miscarried by despondency, and been strangled in the birth by a cowardly imagination?"

"This is brave Bear-Garden language!"

"Everyone has a fair turn to be as great as he pleases."

"People's opinions of themselves are commonly legible in their countenances."