ARIEL SHARON'S CURRENT COMA may highlight debates on how to reconcile ancient Jewish halakhah with modern medical technology. This A.P. article has some reflections:

In Israel, physicians typically defer to families or patients about whether the treatment should follow secular or religious codes.

Many rabbis follow a 1986 decision by Israel's chief rabbinate - the government's highest religious authority - that defines death as irreversible inactivity of major parts of the brain stem, which controls breathing, swallowing and other basic bodily functions.

The opinion is based on various Jewish texts including the Mishnah, an early source of rabbinical tradition, which establishes decapitation as an irrefutable sign of death. In the modern sense, the rabbis interpret a nonfunctioning brain stem as the same thing.

But others see the core of life in the heartbeat, which can occur even with a severely damaged brain stem and can continue with artificial respiration. Some rabbis cite ancient texts that say death occurs only when there is both no respiration and no "movement" in the body. They consider a heartbeat a life-signifying movement even if maintained through life-support and may counsel followers not to remove life support.

[...]

The issues are so delicate that it took six years for Israel's top rabbinical scholars, physicians and other experts to hammer out legislation to allow the terminally ill to refuse life support. It passed last month with one unique provision: the equipment could only be turned off by an automatic timer to avoid having a health care worker do it.