The definition of human life is a profound cultural and political fault line. One end, of course, is when human life begins. This surfaces as a largely emotional debate, and facts don't enter into it very much. For example,here is Zack Beauchamp in Vox, discussing why white evangelical Christians find such an unlikely hero in the Resident. It turns out it's because they're racists, but we already knew that. However, he concludes with this:
While it is true that Jesus didn't hate "the undocumented" (and of course back in his day there generally weren't any visas or passports or border patrols), it is not the case that the Bible prohibits abortion. Beauchamp, who writes about politics for a living, evidently doesn't know that. In fact there is not one word about abortion in the Bible, New Testament or Old, with the possible exception of a passage in Numbers which some people interpret as a ceremony for the purpose of inducing abortion. The public debate about the subject would be better served by the introduction of some facts, of which that would seem to be an important one.Typically, you expect evangelical ideas to flow from religion to politics: They have a deep belief that the Bible prohibits abortion, for example, and support bans on legal abortion as a result. But in this case, Sheila and Linda aren’t starting from scripture; there’s no biblical reason to think Jesus hated the undocumented.Instead, it’s the other way around. The sense of existential threat — that “the survival of the Christian nation” is at stake — is leading them toward a particular, racialized definition of what their faith means. The evangelical right, and the American right more broadly, is being reshaped to match the white backlash politics that powered Donald Trump’s rise.
However, what I really want to talk about today is the other end of the fault line, when life ends. Robert Truog and colleagues in JAMA discuss the history of the concept of brain death. For millions of years of hominid existence, there was never any problem deciding when a Homo erectus or Homo sapiens was dead. If you aren't breathing, that's all I need to know.
But in the 1950s, humans invented positive pressure ventilation, which made it possible to pump air into the lungs of people who, as Truog et al put it, "had no discernible cognitive function." So were these people dead? When was it okay to pull the plug. In 1968 an ad hoc committee at Harvard Medical School decided that "irreversible coma" was equivalent to death. They concluded that this could be established if "over a 24 hour period, the patient did not respond to stimuli, had no spontaneous movement or breathing; and had no reflexes; a flat electroencephalogram provided valuable confirmation of the cessation of brain function."
Some people think that the desire to get transplantable organs influenced this decision, but it seems pretty reasonable on the face of it. Over the ensuing years, states began to write these criteria into law, and now it more or less pertains in all 50. However, as we have seen, not everyone accepts this, and controversies keep erupting over decisions to withdraw "life support" from people who, according to the law, are actually dead.
Originally, defenders of the criteria argued that even if brain dead people were kept on life support, their bodies would quickly deteriorate and the heart would stop. It turns out, however, that this is not really true. It is technically possible now to keep the hearts of brain dead people beating for years. In 2008, a presidential commission proposed that brain dead people are not alive because they have ceased to perform "the fundamental vital work of a living organism." But this creates a problem because many people who are not brain dead require assistive devices to perform said "vital work."
The fact is that for some reason people don't want to grasp the nettle -- on both ends of the debate. What makes us human is not our beating heart or our pumping lungs, it is our consciousness, our capacity to experience. This requires, at a minimum, a functioning frontal cortex. There is no ghost in the machine, the machine is indistinguishable from the ghost. They are one and the same. Everybody needs to get that before we can have a sensible discussion.