Bioethics Blogs

Head Transplants, Personal Identity, and Derek Parfit

by J.S. Blumenthal-Barby, Ph.D.

In a recent article in New Scientist (, Italian neurologist Sergio Canavero claims that the first human head transplant could occur as early as 2017. He plans to announce his project at the American Academy of Neurological and Orthopaedic Surgeons conference in June. Here I set aside assessment of the scientific and medical merit behind this plan (though it is of note that this procedure was performed on a monkey who lived for 8 days), and I also set aside assessment of the broader ethical issues associated with this idea, and focus more narrowly on the issue of personal identity—though personal identity is of course an ethical issue as well as a metaphysical one.

For those of us who are philosophers, the announcement garnered intrigue given that one of the world’s most well-known living philosophers, Dererk Parfit, has written extensively in the philosophical literature on this idea. In his early work, Reasons and Persons, Parfit aimed to work out an answer to the question of what makes someone the same person over time (i.e., the question of personal identity in a numerical sense). Options include the continuity of a metaphysical immaterial substance such as the soul, the continuity of the body or the human animal self, or the continuity of one’s psychological make-up or thinking self. Parfit favors a psychological continuity criterion for personal identity. What “matters,” really, is connectedness of memories, desires, intentions, etc. over time. Though I certainly have different memories and intentions at the age of 35 as I did at the age of 15, at each time point that led up to the present, there was overlap and connection between these memories, desires, beliefs, etc.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.