If you don't have a nasty obituary you probably didn't matter.

Dropping of the atomic bomb was the main subject of conversation for many years and so people had very strong feelings about it on both sides and people who thought it was the greatest thing they'd ever done and people who thought it was just an unpleasant job and people who thought they should have never done it at all, so there were opinions of all kinds.

The total disorder in the universe, as measured by the quantity that physicists call entropy, increases steadily over time. Also, the total order in the universe, as measured by the complexity and permanence of organized structures, also increases steadily over time.

Technology is a gift of God. After the gift of life it is perhaps the greatest of God's gifts. It is the mother of civilizations, of arts and of sciences.

The purpose of thinking about the future is not to predict it but to raise people's hopes.

One of the memorable moments of my life was when Willard Libby came to Princeton with a little jar full of crystals of barium xenate. A stable compound, looking like common salt, but much heavier. This was the magic of chemistry, to see xenon trapped into a crystal.

The Ph.D. system was designed for a job in academics. And it works really well if you really want to be an academic, and the system actually works quite well. So for people who have the gift and like to go spend their lives as scholars, it's fine. But the trouble is that it's become a kind of a meal ticket - you can't get a job if you don't have a Ph.D.