Brownson: if your brain is transplanted into another body, you are the one who wakes up
The Brownson case
A person goes where their mental life goes: personal identity follows psychological continuity (realized in matter, here the brain), and not the continuity of the body.
Brownson has Robinson's body but Brown's memories, and we say he is Brown: a person follows their mental life, not their body.
"Brownson: if your brain is transplanted into another body, you are the one who wakes up" is an argument by Sydney Shoemaker (Self-Knowledge and Self-Identity (1963); "Personal Identity: A Materialist's Account" (1984), 1963) on the question "Who am I, really?" (answer: my consciousness, my memory). Its claim: A person goes where their mental life goes: personal identity follows psychological continuity (realized in matter, here the brain), and not the continuity of the body. According to AskPhilosophy's logic check (Z3 solver), the argument is valid only if one grants a premise the author leaves unstated (P4). AskPhilosophy presents 4 objections, 0 of them with a documented reply, and the original text behind each premise, checked word for word.
Brown and Robinson are operated on for brain tumours; both brains are removed and, by mistake, the assistant puts Brown's brain into Robinson's head, and the other way round. One of the two men dies at once. The other, who has Robinson's body and Brown's brain, wakes up: he is called "Brownson". He recognises Brown's wife, tells Brown's life as his own and knows nothing of Robinson's. Shoemaker (1963) notes that many of us would say Brownson is Brown in Robinson's body; and then we would not be taking bodily identity as the criterion of personal identity. He stays cautious: the case is imaginary, and what people would say is a matter of fact. In the 1984 debate with Swinburne, he defends psychological continuity, realized in matter.
click a premise to reject it
Without the implicit premise: Without P4, the computer finds a case where people judge that Brownson is Brown, and the judgement proves nothing about identity: for instance because it comes from a habit of speech that would change if we were given other reasons.
Objections
4Each objection is a conversation: click to see who replies and where the debate stands.
Sydney Shoemaker himself 1963 · attacks premise 4Shoemaker notes that the question of what most people would say if the imagined events occurred is a factual question, not one for philosophers to decide. And he adds that one could not say these people would be mistaken: they would only have adopted new criteria of personal identity, different from ours today. The case does not discover the true criterion, it shows a possible one.
no reply
Shoemaker notes that the question of what most people would say if the imagined events occurred is a factual question, not one for philosophers to decide. And he adds that one could not say these people would be mistaken: they would only have adopted new criteria of personal identity, different from ours today. The case does not discover the true criterion, it shows a possible one.
Bernard Williams 1970 · attacks premise 4Williams takes up the body swap but tells it differently: you are told that after the operation, the person who has your body will be tortured. The stories give opposite judgements, depending on whether the situation is described in terms of character or of future pain. The spontaneous judgement cannot therefore serve as reliable evidence.
no reply
Williams takes up the body swap but tells it differently: you are told that after the operation, the person who has your body will be tortured. The stories give opposite judgements, depending on whether the situation is described in terms of character or of future pain. The spontaneous judgement cannot therefore serve as reliable evidence.
EEric Olson 1997 · attacks premise 3We are human animals. An animal persists as long as its biological life continues, whatever its mental life. Psychological continuity is therefore neither necessary nor sufficient for us to persist. The intuition that one "follows" one's brain, so strong in transplant cases, concerns what matters to us, not what we are.
no reply
We are human animals. An animal persists as long as its biological life continues, whatever its mental life. Psychological continuity is therefore neither necessary nor sufficient for us to persist. The intuition that one "follows" one's brain, so strong in transplant cases, concerns what matters to us, not what we are.
Derek Parfit 1984 · attacks premise 3Psychological continuity can divide: if your brain is shared between two bodies, or a duplicate is made, there are two persons with your mental life, and they cannot both be you. Parfit concludes that identity is not what matters, and that psychological continuity is enough without being identity.
no reply
Psychological continuity can divide: if your brain is shared between two bodies, or a duplicate is made, there are two persons with your mental life, and they cannot both be you. Parfit concludes that identity is not what matters, and that psychological continuity is enough without being identity.