It was one time when people thought the value of the fine structure constant was important. Now of course it's still important, of course, as a practical matter,but we now know that the value it has is a function, that in any fundamental theory you derive the fine structure constant as a function of all sorts of mass ratios and so on and it's not really that fundamental.

As you learn more and more about the irrelevance of human life to the general mechanism of the universe, the idea of an interested god, becomes increasingly implausible.

If (the antiproton) had not been discovered, the foundations of physics really would have crumbled.

Maybe nature is fundamentally ugly, chaotic and complicated. But if it's like that, then I want out.

I don't need to argue here that the evil in the world proves that the universe is not designed, but only that there are no signs of benevolence that might have shown the hand of a designer.

I now want to tell three stories about advances in twentieth-century physics. A curious fact emerges in these tales: time and again physicists have been guided by their sense of beauty not only in developing new theories but even in judging the validity of physical theories once they are developed. Simplicity is part of what I mean by beauty, but it is a simplicity of ideas, not simplicity of a mechanical sort that can be measured by counting equations or symbols.

Quantum field theory, which was born just fifty years ago from the marriage of quantum mechanics with relativity, is a beautiful but not very robust child.