More on Personal Identity. Daniel Dennett. Co-director of the Center for Cognitive Studies at Tufts. Professor of philosophy at Tufts. One of the “Four Horsemen of the Atheist Apocalypse.”. Dennett’s Dangerous Mission.
The US was trying to tunnel through the Earth to attack the Soviet Union “from below” with a nuclear weapon.
They didn’t get very far, and now the weapon is stuck under Tulsa, Oklahoma.
Unfortunately, the device is emitting a special kind of radiation that completely destroys brain tissue (but no other living tissue).
Dennett is tasked with retrieving it.
Then, they’ll record all of it’s output signals
Finally, they’ll hook Dennett’s body up to respond to the output signals.
Also, Dennett’s nerves/ sensory organs will broadcast the brain’s inputs back to it.
“In a brain transplant operation, one wanted to be the donor, not the recipient. Better to call such an operation a body transplant, in fact.” p. 220
Maybe, then Dennett is his brain.
A first problem is that he doesn’t seem to be over there (to himself).
But maybe that’s misleading.
Dennett says there’s another problem, though.
Suppose Dennett’s body, while under the control of his brain, goes and robs a bank.
I’m free! brain, goes and robs a bank.
I’m in jail! brain, goes and robs a bank.
Maybe Dennett is wherever his point of view is. So in the brain transplant case, he’s the recipient, because that’s where his point of view is (where he seems to be). And in the current case, he’s the remote-controlled body, because that’s where he seems to be.
Dennett concludes that “Where am I?” is a difficult question to answer.
Dennett goes off to fix the problem with the nuclear warhead. But the radiation is interfering with his radio signal:
“There I was, deaf, dumb, and blind, in a radioactive hole more than a mile under Tulsa. Then the last of my cerebral radio links broke, and suddenly I was faced with a new and even more shocking problem: whereas an instant before I had been buried alive in Oklahoma, now I was disembodied in Houston.” p. 224
One year later, they succeed in getting Dennett a new body.
It’s not the same as the old one… but it’s close.
The researchers explain that they’ve created a computer “duplicate” of Dennett’s brain. Dennett’s body has been broadcasting “input” to both his brain and the computer brain. But the output is only controlled by his own brain. However, the scientists monitor the outputs for both and they’re exactly the same.
The scientists explain that there is a switch that Dennett can flip, which will change which source his body receives instructions from.
Dennett gives it a chance and flips the switch…
“Nothing happened. A click and that was all.”
Dennett’s only worry is that they could hook up one of the Dennett brains (the computer one or the regular one) to some other body, and then someone else would know all of Dennett’s secrets.
Immediately, the inputs would diverge (because I’m not Dennett), and then the outputs would diverge (because what the brain decides to do depends on the information it’s getting from the environment).
Still, both bodies would behave like Dennett, and remember what Dennett remembered.
The dramatic conclusion… “duplicate” of Dennett’s brain. Dennett’s body has been broadcasting “input” to both his brain and the computer brain. But the output is only controlled by his own brain. However, the scientists monitor the outputs for both and they’re exactly the same.
Suppose the teletransporter malfunctions and fails to destroy my body, even though it succeeds at creating a new one just like it on the planet.
The Ship of Theseus:
The Yes/No Principle maintains that there is always a fact of the matter about whether I exist. We can ask of anyone who does exist: Is this person Michael? And there will either be a Yes answer or a No answer (even if we don’t know what the answer is).
If we accept the Yes/No Principle, and we accept that my replica is not me, then we will be forced to say that there is a specific point in the Physical Spectrum where the replacement of one cell causes me to cease to exist.
Parfit thus rejects the Yes/No Principle. Instead, he says there are possible cases where there is no fact of the matter whether I survived or died. It’s not true that this person is me, and it’s not false either.
“I may ask [in the TTP case], ‘Will that person be me?’ But that is a misleading way to put my question. It suggests that I don’t know what’s going to happen. When I know these other facts, I should ask, ‘Would it be correct to call that person me?’ That would remind me that, if there’s anything that I don’t know, that is merely a fact about our language.”
Sometimes disagreements aren’t disagreements over facts.
Some people claim to have been electrocuted. I don’t think they have been, but not because I dispute any of their factual claims.
If we find an intelligent alien or a robot, there is a real factual question as to whether it has conscious experiences or not. We may not be able to ever find out, but there is a real fact.
Parfit thinks this is not true in the difficult personal identity cases. There’s nothing that we don’t know.