genetic engineering is really a form of time travel. It speeds up the natural gradual modification of DNA. Instead of countless generations grounding out the best adaptations, taking millions of years and countless suffering and death, we cut to the chase. We tweak the DNA ourselves into what we need it to be. We have to be careful not to make mistakes.

We will make them anyway, of course. But we can fix them quickly, much more quickly than nature. Time and nature themselves are passing the torch to us, if we will only have the courage to risk being singed by it.