Who Am I?

[QuietSun]

In my philosophy class we recently read Dennett's "Who Am I?" (available on the Web.) My philosophy Instructor modified Dennett's story to the following and I need some help in answering the question at the end.

Suppose, as in the article, Dennett’s brain is removed and controls his body through radio transmission. Dennett’s body is sending information to both his brain and another brain, perhaps a cloned brain. Additionally, let us suppose that this has been the situation since Dennett’s tenth birthday - his body is not in a tunnel under Oklahoma. Twenty years after the start of their “experiment”, scientists decide to reunite Dennett’s body and brain. They also put the cloned brain into a body that is just like Dennett’s current body (part of the thought experiment is the assumption that the scientists have technology capable of this). Let’s call the Dennett-body-Dennett-brain person “A”, and the copied-body-cloned-brain person “B”. B and A are definitely two different persons. They can go about their lives in different countries, experience different things, develop different goals, and even meet each other and marvel at how similar they look (they are not aware of the situation). Now, up until the age of thirty, the brains of A and B have the same beliefs, desires, goals, and so on. We have a lot of evidence that psychology is formed by a combination of experience and biology, and up until their thirtieth year, Dennett’s brain and the cloned brain have exactly the same experiences and biology. Their psychology will be the same at thirty, but then diverge once they are receiving information from different bodies - their experiences will be different (if only due to their different perspectives). The problem is that even though A and B are different persons after the age of thirty, they are psychologically continuous with each other before the age of thirty, and psychological continuous with the individual to whom the procedure performed; let’s call this person “C”. According to the psychological-continuity theory, since A is psychologically continuous with C, A is the same person as C. But, since B is psychologically continuous with C, B is the same person as C as well. To say A and C are the same person is to say there is just one person that we’ve called two different names (like Clark Kent and Superman are the same person). So, A and C are just one person, and B and C are just one person. This means that A and B should be just one person. But they aren’t. So, the psychological continuity view seems to lead to an absurd conclusion - it entails that two clearly different persons are the same person.

Thoughts?

Thanks,
QuietSun

[Jason Clark]

You're right, it is an absurd conclusion. They aren't the same person they're just two people who look and think alike.

You're saying that 'C' is the hypothetical person that 'A' and 'B' would have been if they hadn't had their brains put into seperate bodies?

But they were placed in seperate bodies, 'C' doesn't exist, and they are not the same person.

At least that's what I think. :thumb:

[stevencarrwork]

03-08-2003 @ 01:10 PM
Jason Clark:

You're right, it is an absurd conclusion. They aren't the same person they're just two people who look and think alike.

You're saying that 'C' is the hypothetical person that 'A' and 'B' would have been if they hadn't had their brains put into seperate bodies?

But they were placed in seperate bodies, 'C' doesn't exist, and they are not the same person.



What would happen if A died and was later resurrected into a transformed, glorified body? Would that person still be A?

[Pereynol of Sheer Dread]

This is an interesting bit of speculation, not unlike some of the ideas fostered by Derrick Parfit in his Reasons and Persons. One of Parfit's fantasies upon the problem of personal identitiy involved a machine that would destroy one's body and mind at a location where one was and replicate body and mind in another location. In the book, I think people conceived of this device as a way to "travel" to Mars and back. And the process did look like traveling; as the body/mind was destroyed on one end, there was no pain, and as body/mind were replicated on the other end---on Mars---it would seem as if it were nothing more than an arrival, because all one's experiences would be reproduced. The knowing subject wouldn't detect a thing. All uses of this machine went well; to the users, it would have seemed something like the "transporters" on Star Trek.

However, Parfit creates acomplicated case involving a specific fictional man. He's never used the machine before, and he's nervous. He's at home with his wife the night before he's supposed to use the machine and his wife reassures him. She's used the machine scores of times, and she's just fine. The next day, the man walks into the machine himself, ostensibly to "go" to Mars, but the machine malfunctions. To him, it seemed as if nothing happened, but the scientists who operate the machine tell him it failed to destroy his body as it should have but it nevertheless replicated his body and mind on Mars. The man was then remarkably allowed to talk to "himself" on Mars. To the replicant, it felt as if he had just left earth, with no complications. A further snag was made known to the original man on earth whose body/mind hadn't been destroyed---his heart had been damaged in the machine, and he hadn't long to live.

As I considered Parfit's book, I had no trouble seeing these two men, the one on earth and the one on Mars as two distinct persons because they didn't share a unified consciousness, or, as you say, they lacked psychological continuity. Yet, if one defines the essence of individuality in terms of information---genetic, contents of memory, and psychological continuity, then there obviously would have been some overlap in both Parfit's and Dennett's scenarios, but it isn't clear that the overlap would be sufficient to substantiate identity, whether numerical or qualitiative. In Dennett's fantasy, might not the the second brain act and supply some divergent elements of consciousness since brains are not simply passive receptacles? Even in the case of cloning, there would most likely be physical differences between the two bodies and brains as well, and obviously theywould be composed of different matter.

My main objection to Parfit involved the fact that his two men lacked psychological continuity, and that for the two persons to be unified would require them to participate in each other's subjectivity or consciousness in a way reminiscent of the Christian Trinity. Dennett's scenario seems remarkable trinitarian, if one looks at it metaphorically....

One further suggestion---you might want to look up a philosopher called Trenton Merricks, who studied with Plantinga and now teaches at the University of Virginia. He is a Christian who specializes in philosophy of mind and takes upon personal identitiy, among other things. He published a book on Oxford UP called Objects and Persons, and he's written some good articles as well.

[Jason Clark]

Teleportation, yay, finally something I understand.

Steve, I think 'A' would still be 'A' but uber'A' too perhaps.

Perhaps I'm just not wired for philosophy. :argh:

[Captain Ochre]

The Dennett scenario ducks out of one of the crucial aspects of the problem, imo. Is the consciousness of a person divisible in the first place? If we assume for the sake of argument that it is, the conclusion will end up with that premise (unless it is contradictory, perhaps).

Suppose that both brains share consciousness, and the thought-experiment takes a different course. We end up with two bodies controlled by (and feeding sense impressions to) one consciousness. More than one "person"? It doesn't appear so.

[edit to add]
Dr. McCoy (STTOS) hated the transporter for exactly the reasons touched on in the thread. He wasn't confident that he would be himself at the other end. This was only barely hinted at in the television show, but emphasized in the early books.

[Pereynol of Sheer Dread]

03-08-2003 @ 03:27 PM
Captain Ochre:

The Dennett scenario ducks out of one of the crucial aspects of the problem, imo. Is the consciousness of a person divisible in the first place? If we assume for the sake of argument that it is, the conclusion will end up with that premise (unless it is contradictory, perhaps).

Exactly so. Can consciousness become multiple and yet keep the integrity of identity intact? If consciousness were multiple and yet psychologically continuous, would it not approach something akin to the Trinity? This question remains speculative, of course, because we lack any sort of mechanistic knowledge about the relationship between the persons of the Trinity pertaining to consciousness, but Dennett's speculations are still strikingly reminiscent of Christian theology in an ironic sort of way.


Suppose that both brains share consciousness, and the thought-experiment takes a different course. We end up with two bodies controlled by (and feeding sense impressions to) one consciousness. More than one "person"? It doesn't appear so.

[edit to add]
Dr. McCoy (STTOS) hated the transporter for exactly the reasons touched on in the thread. He wasn't confident that he would be himself at the other end. This was only barely hinted at in the television show, but emphasized in the early books.

Excellent points.

[QuietSun]

Some interesting points so far, but no one has answered my question. Let me rephrase in my own words.

The question is dealing with Locke's theory of "psychological continuity." Does the following disprove Locke's theory?

We have person C who is unchanged from age 0-10. At age ten we clone C's brain, and from 10-30 C has two brains. At age 30 we reunite C's original body and brain (person A), and put the other (cloned) brain in a cloned body (person B).

We know that A has psychological continuity with C, and we know that B has psychological continuity with C. However, since A and B will now have separate experiences, can travel to different locations etc., we also know that A and B will not have psychological continuity.

So we now have the equation A=C, and B=C, but A does not = B. Does this invalidate the theory of psychological continuity?

(For the sake of this illustration we are assuming that cloning both mind and body is possible.)