I’d quibble with that view of life. If you’re not living for yourself — and not even primarily for your dependents or whomever — you’re here for the duration. Without doing anything extraordinary, you keep yourself as well as you can to do as well as you can — and by that I definitely don’t just mean financially. I know plenty of elderly people who could not be described as superfluous. In fact, I’ve never actually known a human being I could describe that way.