I’ve been thinking a lot about age lately. With the illustrious twenty first birthday nipping at my heels, I’ve looked around and found that I’m surrounded by rap music blaring out of stereos, the endless pages of my biochemistry textbook, red plastic cups aligned in a triangle, and the struggle to not trash my body with food and booze by age twenty-two. Somewhere around age thirty the signature red plastic cup will be replaced by a baby bottle and somewhere around fifty-five I will probably start listening to country music. The things that characterize those ages and my age now are fairly predictable. But what happens when I turn eighty? Since embarking on a pursuit of optimizing my chances to live until I’m at least a hundred years old, eighty is something I need to think about.