The difference, of course, is that Kevorkian’s clients asked for it. That free choice is what separates assisted suicide from murder, his defenders would insist.

But this means that the moral case for assisted suicide depends much more on our respect for people’s own desire to die than on our sympathy for their devastating medical conditions. If participating in a suicide is legally and ethically acceptable, in other words, it can’t just be because cancer is brutal and dementia is dehumanizing. It can only be because there’s a right to suicide.

And once we allow that such a right exists, the arguments for confining it to the dying seem arbitrary at best. We are all dying, day by day: do the terminally ill really occupy a completely different moral category from the rest? A cancer patient’s suffering isn’t necessarily more unbearable than the more indefinite agony of someone living with multiple sclerosis or quadriplegia or manic depression. And not every unbearable agony is medical: if a man losing a battle with Parkinson’s disease can claim the relief of physician-assisted suicide, then why not a devastated widower, or a parent who has lost her only child?