I'm in my late 60's, so I suppose I'm already old. Fortunately I'm in good shape at the present time. But as I get older I hope I have the wisdom to:
know when I should stop driving a car and hand in the car keys; know when it's time to hire a caregiver or move into an assisted living facility; and if I become terminally ill, know to tell the doctors to stop trying to extend my life. I have an advance directive just in case.