The last few centuries have seen the world freed from several scourges-slavery, for example; death by torture for heretics; and, most recently, smallpox. I am optimistic enough to believe that the next scourge to disappear will be large-scale warfare-killed by the existence and nonuse of nuclear weapons.

[My father] advised me to sit every few months in my reading chair for an entire evening, close my eyes and try to think of new problems to solve. I took his advice very seriously and have been glad ever since that he did.

The last few centuries have seen the world freed from several scourges-slavery, for example; death by torture for heretics; and, most recently, smallpox. I am optimistic enough to believe that the next scourge to disappear will be large-scale warfare-killed by the existence and nonuse of nuclear weapons.

I'm convinced that a controlled disrespect for authority is essential to a scientist. All the good experimental physicists I have known have had an intense curiosity that no Keep Out sign could mute. Physicists do, of course, show a healthy respect for High Voltage, Radiation, and Liquid Hydrogen signs. They are not reckless. I can think of only six who have been killed on the job.

There is no democracy in physics. We can't say that some second-rate guy has as much right to opinion as Fermi.

I don't like to say bad things about paleontologists, but they're not very good scientists. They're more like stamp collectors.

Dirac politely refused Robert's [Robert Oppenheimer] two proffered books: reading books, the Cambridge theoretician announced gravely, "interfered with thought."