We were sitting in Grant’s office one afternoon talking about efficiency, when he said: “The truth is, I don’t care how many articles I publish or how many words I write. Productivity is an imperfect way of indexing how much I’m contributing, how I’m using my limited time to make the most difference.”

It wasn’t until I was transcribing the conversation a few days later that I realized that when he referred to his limited time, he wasn’t just talking about a busy schedule; there was a more existential tug in the phrase. I brought it up with him by phone.

“It’s the kind of thing I almost never talk about,” Grant said. “But my responsibility is to be open.” Mortality, he said, was the one subject that gave him something like panic attacks. He had always felt that way, since he was a brainy, sensitive kid playing basketball in his driveway, staring at the sun, suddenly terrified of what would happen when it burned out. That was why he first wanted to be a scientist — before he realized biology bored him and he would never reinvent physics — so he could help figure out how to extend life, or at least design the spacecrafts that he is sure, even now, will take us to safer planets if this one runs dry. Mortality, he said, is “something I can’t fix. I can’t do anything with or about it.” He can’t let himself think about it too much; he has lost days at a time to his anxiety, “to the point that it’s the equivalent of extreme physical pain.”

http://www.nytimes.com/2013/03/31/magazine/is-giving-the-secret-to-getting-ahead.html?_r=0