I'm not sure where I stand on the issue - I just wanted to state my uncertainty - but I thought you might find this article interesting.

Particularly: "The church doctrine, and it’s been consistent for 400 years, is that one is not morally obliged to undergo any intervention. And, of course, 400 years ago they weren’t talking about high technology. Here’s the example one of the moralists of the 16th century gave: if you could sustain your life with partridge eggs, which were very expensive and exotic, would you be obliged to do so? The answer is no, they’re too expensive. They’re too rare. You can’t get them. They would be too heavy an obligation to put on people...

[The Pope] said even such things as artificial nutrition and fluid can become extraordinary if they become burdensome when you have to sustain somebody for 15 years on it. That’s surely burdensome. It has nothing to do with the technique itself. Antibiotics could be extraordinary if a patient is dying and it’s not going to offer many benefits. The bishops of Florida themselves have addressed this issue of the papal statement. Right-to-lifers aren’t attacking this Jesuit priest, me; they’re now attacking all the bishops of Florida saying they are deviating from the pope. What the right-to-lifers want to say is the pope said you must always use artificial nutrition and fluids for patients in persistent vegetative state—and there’s no exception. The Florida bishops say that’s not what the church has taught and that’s surely not what this means.

**********

Certainly this doesn't make or break the issue for me, but it is interesting. So is the fact that the Pope has no known living will.