It's possible that we could change a human gene and double our life span. I don't know if that's true, but we can't rule that out.

In the early '90s, we discovered mutations that could double the normal life span of worms.

Generally, older people in their fifties, sixties, and seventies are running most countries and are CEOs of corporations. Which isn't to say there aren't entrepreneurs, but if the young were better in every respect, there'd be no reason for the old. Our life span reflects our particular life strategy.

In one century, we've added 28 years to our average life span - a change so rapid that our brains couldn't possibly have evolved to accommodate it.

When you extend life span, that's really something. That's hard to do.

Retarding the aging process would be therapy and enhancement because it would mean defeating diseases and because it would extend our life span.