I think because it seemed hard, and because it seemed comfortingly objective. I had gotten myself into this incredible existential funk as a child about moral relativity and animal rights-- I had a crazy animal rights and environmental magazine was pathologically invested in it, and also completely convinced that I was going to start a revolution among young people, like other 10- and 11-year-olds. But when I went to public high school I realized that not everyone agreed with me. Everyone wasn't a crazy hippie. I thought, "How do I know I'm right and everybody's wrong?" And so I turned to the sciences. It's also where you get that feedback loop, academically: positive reinforcement, good grades, stuff like that, and it's so easy to climb. That was something completely new to me, having grades, having gold stars. I got into that.