We can summarize electricity, magnetism and gravity into equations one inch long, and that's the power of field theory. And so I said to myself: I will create a field theory of strings. And when I did it one day, it was incredible, realizing that on a sheet of paper I can write down an equation which summarized almost all physical knowledge.

To understand the difficulty of predicting the next 100 years, we have to appreciate the difficulty that the people of 1900 had in predicting the world of 2000.

When I was 16 years old, I assembled a 2.3 million electron volt beta particle accelerator. I went to Westinghouse, I got 400 pounds of translator steel, 22 miles of copper wire, and I assembled a 6-kilowatt, 2.3 million electron accelerator in the garage.

In science, nothing is ever 100% proven.

Srinivasa Ramanujan was the strangest man in all of mathematics, probably in the entire history of science. He has been compared to a bursting supernova, illuminating the darkest, most profound corners of mathematics, before being tragically struck down by tuberculosis at the age of 33, like Riemann before him. Working in total isolation from the main currents of his field, he was able to rederive 100 years' worth of Western mathematics on his own. The tragedy of his life is that much of his work was wasted rediscovering known mathematics.

For relaxation, I like to figure skate. Being on the ice and spinning and jumping, I feel very close to nature. In particular, I feel very close to Newton's laws of motion. On the ice, you can experience Newton's laws of motion in their purest, most elegant form.

I realized very early in life what my abilities and limitations were, and foreign languages was definitely one of my limitations. With strenuous effort, I just barely passed my French class at Harvard so I could graduate.