I think just because you can do something to prolong someone's life, there used to be a time when a good doctor knew this didn't automatically mean you should.

I know my grandparents didn't fear or refuse to believe in death in the same way as people do now (and they had seen a lot of it). I hope I'm strong enough and happy enough with myself that I will gladly relinquish my hold on the reins of life when its properly time to do so, and not fear it or be sad.