But the beauty of Einstein's equations, for example, is just as real to anyone who's experienced it as the beauty of music. We've learned in the 20th century that the equations that work have inner harmony.

Even before string theory, especially as physics developed in the 20th century, it turned out that the equations that really work in describing nature with the most generality and the greatest simplicity are very elegant and subtle.

Ragtime was a fanfare for the 20th century.

Sex is the ersatz or substitute religion of the 20th Century.

I live in the 20th century. I have copper rivets on my jeans.

In the 20th century, the Muslim world created a vision of religious nationalism. Turkey, for example, had to be ethnically Turkish. Kurds, Armenians, other minorities didn't have a place in such a vision of a nation-state.