philechat

i.e. Our genetics will determine how each brain cell relates to another, giving it a specific "structure" which is the origin of our consciousness. These hard-wirings remain similar, if not the same, throughout our lives. Our experiences are specifically stored as memory of past events in a given part of the brain that is susceptible to structural changes, whereas the unchanged areas in the brain interpret the changed structures of those memory locus and give rise to the concept of identity.

There are instances where this interpretation process are interrupted, however, such as during sleep or intense mood disturbances. It may not be merely metaphorical to say "he is not himself right now because of grief."

luvluv

Not that I have any intention of getting into this can of worms, but I read once that we are totally renewed every seven years. You will be composed of totally different matter seven years from now, brain cells included.

yguy

I would say yes, on the basis that thoughts, memories and personality traits are no more indispensable to my personhood than my right arm is. As evidence for the validity of this postulate, I offer the fact that thoughts may be observed objectively by the core self, and that personality traits may be bypassed in time of need by the core self. For instance, if you are a gregarious person, you will inevitably meet someone to whom this trait signals an opportunity to take advantage of you, in which case you do well to not to direct it at that person.

Clutch

Your first premise is false.

At a minimum, there is nothing irrational about holding the following: The changes that take place in the time one reads a sentence are normally very small. (Though it depends on the sentence! Yours didn't do much for me, as it turns out, but many people have become very different indeed over the few minutes it takes to read, say, The Communist Manifesto). Still they are changes nonetheless. People can indeed change enormously over time -- preferences, beliefs, dispositions, memories, emotions... the whole works. These enormous changes are simply aggregates of much smaller changes that happen as a result of virtually all experiences.

Your argument would work just as well to prove that continents never move. Because, after all, Antarctica doesn't move to Asia in the time it takes to read a sentence.

mnkbdky

So if I am reading you right, you believe that something can change a little and still remain the same. Here is a question for you, let's say you lend me a book from you favorite author and this book is, say, 1500 pages long. After I finish the book I return it to you, with one page missing (a small change). Did you receive the same book back that you gave to me? No. The book you gave me had 1500 pages, whereas the book I gave you was 1499 pages.

As for your Antarctica argument, I am not even sure how that applies. However, I think I can salvage something from it. First answer me this, Is there really such a thing as Antartica or is it merely a name we have given to designate a mass of land? Obviously it is latter. We must be careful about reification. That is, we must not make something real that is not. Antartica is a name, unchanging at that--perhaps that is where the confusion lies (or lays, I can never remember), which we give to the land mass, which constantly changes.

Now, I assume Antartica has icebergs (not sure, never been there) and if it has icebergs then I assume that they calve (break off). So if a small chunk of the iceberg on the land mass we call Antartica breaks off and floats away, Is it the same land mass that had it? No. The former land mass had another piece of ice on it.

It is very similar to Heraclitus' statement, "you cannot step twice into the same river" (See, Plato's Crat. 402a).

Guillaume

No, we believe that something can change a little and become a little different, just like something can change alot and become very different.

echoes

The first assumption seems to outright dismiss the bundle theory without seriously arguing against it. That's not all that unexpected as the bundle theory can seem so counter-intuitive to many people as to seem absurd.

Here's my understanding of Parfit, the bundle theory, etc.

In teletransportation, 100% is instantly replicated.

In everyday life, replication is gradual (7 years according to some posters here), but eventually reaches 100%.

Under those two assumptions, Parfit argued the following:

The replica in teletransportation is not you, because you could easily conceive of a situation where there could be multiple replicas and/or the original survives when the replica is produced, which brings about the duplication problem.

Most people would say that if only 1% is replicated, then personal identity is retained. Parfit argued that if this were true, then there would have to be some critical percentage in the middle, such as 50% for example. If 51% is replicated, then identity is lost, but if only 49% is replicated then the replica has the same identity as the original. But Parfit says that this is rather problematic- why should only a few cells either way make such a difference? Therefore, the idea of a critical percentage is absurd.

(As an aside, Parfit also argued against the ego theory on the basis that ego theory requires that critical percentage. I don't really remember the details of that argument too well however.)

Or to give another example, consider the following: A person steps into a fairly primitive teletransporter expecting to be teletransported. Since this is a primitive teletransporter, it cannot complete the teletransportation in one step. The individual is first teletransported to an intermediate teletransporter and only 25% of his body is replicated in the process. He is then teletransported a second time, and another 25% is replicated, for a total of 50%. After two more teletransportations, the procedure is complete. Since he was not conscious during the procedure, he (or perhaps I should say, his replica) is ignorant of the four teletransportations. As far as he knows, he simply pushed the button, and was teletransported in one step.

The identity of the individual leaving the final teletransporter in this scenario is analogous to the identity of the individual leaving the teletransporter in the previous teletransportation scenario. In both cases an individual entered a teletransporter, and some time later, a 100% replica emerged. Now imagine a scenario with ten teletransporters, each of which replicates 10%… or billions of teletransporters, each of which replicates only a tiny fraction of the individual. All of these scenarios produce the same results as the original teletransporter scenario.

What is the difference between being teletransported and replicated billions of times, and going about everyday life with your body cells quietly dying and being replaced? Obviously a teletransporter is an intrusive machine that changes the physical location of a being, but those are mundane details- we could easily conceive of a more subtle method that doesn't change location.

This whole argument leads up to Parfits conclusion, that ordinary survival is no better than being destroyed and replaced with a replica.

Someone please correct my understanding of Parfit and the bundle theory if I've gone astray.

Clutch

You are not reading me right; nor can I see how you might have confabulated such a remarkable interpretation given my quite careful remarks.

Persons change over time. Hence -- ie, this is a restatement -- they are not strictly diachronically identical. In considering only prospects like whether Ted could become Mary over the course of reading a single sentence, you embrace a baffling failure of reasoning. It is analogous to arguing that continents don't drift, since the Americas don't fly to Australia in the time it takes to read a single sentence.

Hume only made this point 300 years ago, so it might still be hot off the press. But it's as correct now as it was then: strictly, identity is identity, and difference is difference. The ongoing real-time changes in persons are (usually!) small, but identity is all-or-nothing. There is no diachronic identity, strictly speaking.

But of course our categories of praise, blame, family membership, legal status and so forth, are deliberately vague enough to tolerate a very good deal of change while still applying. Our most common uses of the diachronic notion of "same person" do not actually incorporate the strict notion of identity.

Michaelson

mnkbdky: Still curious about whether or not my dog in the backyard is the same dog that I gave a bone to this morning?

And in terms of what I was saying before about the tree, couldn't we replace your third premise with something that classified as the same thing so long as it remains the one continuous living system?

yguy: in response to my question about the operation that removes all memory and changes personality. Same person?: Isn't the type of introspection you are talking about absolutely key to the idea of personal identity? Sure, through experience and reflection we can choose to try and change things about ourselves, with regards to what we have learnt for ourselves seems to work best for us. But with the operation this is all taken away. It's not just that our personality has changed, but that we no longer have any reference point for who we were before the operation. There is no continuity of consciousness at all: all that has gone before has nothing to do with who we are now.

If these concerns aren't of central importance when trying to locate personal identity, I'm curious what you would argue are the important considerations?

mnkbdky

Perhaps you think you are clear, but I still have no clue what you are saying about America and Australasia. Explain your continent analogy to me as if I were a three year old.

Am I just a moron? Does this make sense to anyone else? I wouldn't be suprised if it was me.

Futhermore, if identity is all or nothing, then, why when Ted comes in and out of existence--viz. Hume's time-slices--can't the next slice be named Mary? According to Hume time slices are not causally connected, as they are in some Buddhist theories, and, thus, can neither be diachronically nor synchronically the same.

Perhaps you are saying that personal identity is merely a matter of convention, by writing they are not "diachronical identical". If they are not diachronically or synchronically identical, then what are they? It seems you are agreeing with me.