Terri Schiavo, Persistent Vegetative State, and Materialist Neuroscience
Yale neurologist Dr. Steven Novella and I have been involved in a vigorous discussion (example here) of the mind-brain problem in science and philosophy. There are real-world implications of our understanding of the mind, and nowhere are these implications more important than in the medical management of people with severe brain damage. Dr. Novella recently posted a commentary on the Terri Schiavo case. Dr. Novella's post was prompted by a study just published in the journal Neurology that analyzes the media coverage of the affair and offers suggestions as to how experts and journalists can convey the truth of such complex cases to the public more effectively. These are laudable goals.
The crux of the matter, of course, is this: what are the facts in the Schiavo case, and, more generally, what are the real issues involved in the diagnosis of persistent vegetative state (PVS)?
Dr. Novella and I see things quite differently. I am a neurosurgeon, and I believe that the diagnosis of persistent vegetative state, in Ms. Schiavo's case specifically and in other cases more generally, is of dubious validity. "Persistent vegetative state," defined succinctly but accurately, is the denial of subjective experience in a brain-damaged human being. PVS is the medical assertion that a human being is an object, but not a subject.
PVS is the only modern medical diagnosis that denies the personhood of a patient, and thus is fraught with logical and ethical problems. Furthermore, patients diagnosed with PVS are precisely those patients in whom discernment of awareness is most unreliable. We can never directly apprehend the thoughts of other people; we infer the thoughts of others only by their behavior. Patients with severe brain damage are precisely those people in whom expression of behavior is most impaired and in whom diagnoses based on assessment of behavior are most unreliable.
If the mind is entirely caused by the brain, the inference that a severe degree of brain damage could eliminate the mind is unexceptional. If mental causation is in part immaterial, one would approach the inference that brain damage would render a human being an object-but-not-a-subject with great caution. The materialist inference in neuroscience was very much a part of the Schiavo debate, and that inference had--and continues to have--profound ethical consequences.
In my view, the political efforts to save Ms. Schiavo's life were well-intentioned and completely justified. I believe that many of the medical opinions offered publicly by physicians who favored withdrawal of Ms. Schiavo's hydration and nourishment were rank pseudoscience. What was done to Ms. Schiavo was an atrocity.
A detailed and thoughtful public exchange of views about the Terri Schiavo case by two experts in neurological medicine--an academic neurologist and an academic neurosurgeon who have quite different opinions on this matter--would be very informative. The discussion could take the form of detailed exchanges between Dr. Novella and me on specific aspects of the case, such as the autopsy report, the neurological exams, the nature and reliability of the diagnosis of persistent vegetative state, and the ethical and political issues involved. This discussion extends to many of the issues involving the materialist inference in neuroscience that Dr. Novella and I have debated over the past year.
I will begin in the next week or so by discussing the medical aspects of the diagnosis of persistent vegetative state.
I hope Dr. Novella will join me in this important public discussion.