I think science and religion should be separate.

Things are always more complicated than most people believe.

The point of fact is, just in simple ways, you can see how much better things have gotten. I mean, when I was a child, I lived in England, and England was just amazingly polluted. We didn't use that word. We just said it was it all covered with soot.

A good scientist is a person with original ideas. A good engineer is a person who makes a design that works with as few original ideas as possible. There are no prima donnas in engineering.

We do not know how much of the environmental change is due to human activities and how much [is due] to long-term natural processes over which we have no control.

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.

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.