In light of the recent events involving Terri Schiavo and suffering in general, I think the following excerpt from page 119 of Deal Hudson's new book: An American Conversion : One Man's Discovery of Beauty and Truth in Times of Crisis is excellent .
Deal is talking about Walker Percy and his novel the Thanatos Syndrome...
...Percy wanted to make the message unmistakable: avoid the pain and suffering of a human life, one constituted by the unity of body and soul, and you risk loosing demons. The very complacency and ersatz happiness produced by disjunction between the mind and body becomes the occasion of the cruel elimination of the unwanted and the imperfect, including children, the handicapped, and the infirm.
At the novel's end, Father Smith preaches what has to be the most powerful homily in modern literature; at its apex he repeats twice the following thought: "'Don't you know where tenderness leads?" Silence. 'To the gas chambers.'" Percy's Father Smith is echoing a comment previously made by Flannery O'Connor in her introduction to A memoir of Mary Ann: "In the absence of faith, we govern by tenderness, and tenderness leads to the gas chamber," Acts of tenderness that extinguish life to eliminate suffering are cruel; they are based on the conclusion that a life isn't worth living if the pain of the body destroys self-satisfaction. Such acts reject not only faith in the goodness of creation but also the unity of the human person. This is not to say that suffering should be regarded as good in itself, but to acknowledge a necessity of finitude and bodily existence. page 119