The most complex object in the known universe: brain, only uses 20 watts of power. It would require a nuclear power plant to energize a computer the size of a city block to mimic your brain, and your brain does it with just 20 watts. So if someone calls you a dim bulb, that's a compliment.

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.

Some people are a little bit afraid about the future because they see all these gadgets and gizmos coming down the pike and they think they're too old to learn all this new stuff. But eventually they begin to realize, 'Hey, some of this stuff is useful.'

We need more concept-development and active involvement, less tuning forks, pulleys, and friction formulas - students know they'll never use those. They need more study of outer space and DNA. They need more exciting teaching, more fair-minded encouragement, more career guidance, more mentorship. Both students and teachers need more feedback. It would help if we stopped protecting bad teachers - It's very difficult to get rid of even sexual perverts let alone just bad teachers.

Today, your cell phone has more computer power than all of NASA back in 1969, when it placed two astronauts on the moon. Video games, which consume enormous amounts of computer power to simulate 3-D situations, use more computer power than mainframe computers of the previous decade. The Sony PlayStation of today, which costs $300, has the power of a military supercomputer of 1997, which cost millions of dollars.

I'm a physicist, and we have something called Moore's Law, which says computer power doubles every 18 months. So every Christmas, we more or less assume that our toys and appliances are more or less twice as powerful as the previous Christmas.

The brain weighs only three pounds, yet it is the most complex object in the solar system.