“Strange as it may seem, wrote Richard Feynman, we understand the distribution of matter in the interior of the Sun far better than we understand the interior of the Earth.”

“The upshot of all this is that we live in a universe whose age we can't quite compute, surrounded by stars whose distances we don't altogether know, filled with matter we can't identify, operating in conformance with physical laws whose properties we don’t truly understand.”

“On a cooler sun on a primordial earth: "I later learned that biologists, when they are feeling jocose, refer to this as the 'Chinese Resaturant Problem'--because we has a dim sun.”

“Physics is really nothing more than a search for ultimate simplicity, but so far all we have is a kind of elegant messiness.”

“People don't talk like this, theytalklikethis. Syllables, words, sentences run together like a watercolor left in the rain. To understand what anyone is saying to us we must separate these noises into words and the words into sentences so that we might in our turn issue a stream of mixed sounds in response. If what we say is suitably apt and amusing, the listener will show his delight by emitting a series of uncontrolled high-pitched noises, accompanied by sharp intakes of breath of the sort normally associated with a seizure or heart failure. And by these means we converse. Talking, when you think about it, is a very strange business indeed.”

“Because we humans are big and clever enough to produce and utilize antibiotics and disinfectants, it is easy to convince ourselves that we have banished bacteria to the fringes of existence. Don't you believe it. Bacteria may not build cities or have interesting social lives, but they will be here when the Sun explodes. This is their planet, and we are on it only because they allow us to be.”

“...if you were designing an organism to look after life in our lonely cosmos, to monitor where it is going and keep a record of where it has been, you wouldn't choose human beings for the job. But here's an extrememly salient point: we have been chosen, by fate or Providence or whatever you wish to call it. As far as we can tell, we are the best there is. We may be all there is. It's an unnerving thought that we may be the living universe's supreme achievement and its worst nightmare simultaneously.”