The distinction between ''passive'' and ''active'' euthanasia, though
problematic and highly criticized, retains a certain intuitive appeal.
When a patient is allowed to die, nature appears simply to be taking
its course. Yet when a patient is killed by, say, a lethal injection,
humans appear to be causing his or her death. Guilt seems to follow na
turally from the latter act while not from the former. Yet this view o
nly holds up if age-old and vague ideas about ''nature'' and ''artific
e'' go unscrutinized. Once examined more closely the functional releva
nce of particular machines to particular bodies becomes evident. And t
he innocence and guilt less clear.