More from the same e-mailer:
The trouble (and the direction in which the fetish of the brain will point) is that insisting on brain activity for personhood means that a person in a coma should be looked upon as a repository of spare parts. And more generally it assumes that what matters about us in the decisive sense is what we can do, rather than what we are. Remember, we are not talking here about a full rich description of the human person; rather we are asking what are the minimal criteria a human being needs to meet for us to decide that this being should not be killed on purpose? I would argue that membership in the species–being a living, functioning, human being–is all it should take to pass such a low bar. If we are in fact to live dedicated to the proposition that all men are created equal, do we mean by that they all have fully functioning brains? I don’t think that’s what we want to say.
But as Hood says, people of good faith do differ.