For [Richard] Feynman, the essence of the scientific imagination was a powerful and almost painful rule. What scientists create must match reality. It must match what is already known. Scientific creativity is imagination in a straitjacket.

It is not true that people who accomplish things don't waste time and that people who waste time don't accomplish things. The very concept is ill-informed. You can't waste time and you can't save time; you can only choose what you do at any given moment.

Intuition was not just visual but also auditory and kinesthetic. Those who watched Feynman in moments of intense concentration came away with a strong, even disturbing sense of the physicality of the process, as though his brain did not stop with the grey matter but extended through every muscle in his body.

We choose mania over boredom every time.

Tiny differences in input could quickly become overwhelming differences in output.... In weather, for example, this translates into what is only half-jokingly known as the Butter- fly Effect—the notion that a butterfly stirring the air today in Peking can transform storm systems next month in New York.

The library will endure; it is the universe... We walk the corridors, searching the shelves and rearranging them, looking for lines of meaning amid leagues of cacophony and incoherence, reading the history of the past and of the future, collecting our thoughts and collecting the thoughts of others, and every so often glimpsing mirrors, in which we may recognize creatures of the information.

The quotation-business is booming. No subdivision of the culture seems too narrow to have a quotation book of its own.... It would be an understatement to say that these books lean on one another. To compare them is to stroll through a glorious jungle of incestuous mutual plagiarism.