Really, a huge part of my quality of life is knowing that I'm doing stuff that makes the world better in various ways-- offsetting some of the ways I make it worse and the resources I use. When I am not able to do this anymore--- what's the point?
George Eastman (founder of Kodak) left the following note explaining his decision to take his own life (at the age of 77, after several years of failing health and chronic pain).