A single definition and criterion of death

Buford first criticizes my 2019 paper by relying upon a view about the permanence of death that no one should hold as it makes death due to extrinsic features. The second criticism involves a description of cerebrum transplants that I don't accept. The continued existence of a transplanted cerebrum doesn't show that the whole brain death criterion hasn't been met as the brainstem-less person has gone out of existence and so no longer has a brain and thus trivially meets the whole brain criterion. Buford's third criticism is that a criterion should be helpful, doctors can make use of it, and legislators can enshrine it in law. I admit that criterion for the death of the person won't be useful when the person dies but animal remains. But the criterion of existence for the person will be met and one can infer from that the death criterion has been met.