On Tue, Feb 19, 2013 at 5:27 PM, meekerdb <meeke...@verizon.net
On 2/19/2013 1:58 PM, Jason Resch wrote:
On Tue, Feb 19, 2013 at 3:39 PM, meekerdb <meeke...@verizon.net
On 2/18/2013 10:49 PM, Jason Resch wrote:
6. Swapping places with someone: In 5 seconds, your mind and
will swap with that of some rich and famous person. Let's say Bill
hope you are ready. 5. 4. 3. 2. 1. The swap is complete. Bill Gates
in your body, with access to your memories and living as you were just
you got to reading this sentence, while you are living as a billionaire
enjoying Bills bank account. Of course, while you are in his body you
have access to his memories. Not only does his wife not notice the
but you don't even notice it. You only have access to Bill's memories
you do not realize anything is awry. Don't worry, everything will be
how it was, in 3. 2. 1. Welcome back. How was it? Of course, you don't
remember. Fortunately, Bill was nice enough to read the last few
you and now they have been placed into your memory. This shows it is
meaningless to say "I wish I could live as X", or "experience a day in
shoes". For all you know, you already are, have, and will.
This, if true, only shows that "you" and "Bill Gates" don't exist apart
your bodies and memories, so that it is nonsense to talk of exchanging
We agree it is nonsense.
For it to make sense there would have to be a "you" soul and a "Bill
soul that switched.
Okay, if no soul involved, then by what means can we talk of you at T1 and
T2, when the two are different in terms of memories and material?
There is a problem with any theories of personal identity two individuals
different times. Inevitably it comes down to some arbitrary measure of similarity.
There are two alternatives, no-self theories of personal identity, in which you are
nothing but a single observer moment, and universalism, which identifies
every conscious entity.
You have been seduced by comp so that you forget the simplest theory -
I haven't forgotten it, I've just come to see that the simplest theory (while perfectly
fine for ordinary scenarios) falls on its face in others. Particularly those involving
duplicates, material replacement, teleporters, amnesia, split brains, etc.
What is physical continuity's answer to the following questions:
Who will you find yourself to be when you awake from a split brain surgery?
Do you experience the perspectives of all your branched copies under the Everett
Would you survive or die when you use a star-trek style transporter?
Do I lose consciousness if I lose access to all my memories?
Can my mind be slowly transformed to that of any other conscious person without losing
If I step into a duplication machine and 10 copies come out, which one do I
Arnold Zuboff gives the following thought experiment to show how inadequate physical
continuity theories are:
I imagined two brains lying at
either end of an operating table. For the sake of vividness - please forgive
me - let us say a mad scientist has only a moment ago snatched the brain
from your head. It is one of the two on the operating table. The other brain
is a precise duplicate of yours in every discriminable respect, including all
its patterns of memory traces. Perhaps the scientist created this duplicate
himself, or perhaps he stole it from the head of one of those duplicates of
you that would have arisen naturally in an infinite universe.
Anyway, this mad scientist is capable of feeding into these brains any
pattern of stimulation he likes, by means of electrodes plugged into them
where nerves would normally be entering from the sense-organs and the
rest of the body. And he has chosen to give both of them precisely the
same pattern of stimulation that your brain would have been receiving if it
had not been snatched from your head moments ago. That would be why
it seems to you that your brain is still in your head, that my paper is still
As I say, both brains are being fed exactly this same pattern of stimu-
lation. What should we expect is true of the subjects and their experience?
Would we not suppose that the episode of experience connected with each
brain would be qualitatively identical? But would we not also think that,
despite the completeness of their qualitative similarity, the subjects and
their episodes of experience must be numerically distinct from one another?
You are one subject, lost in one experience; at the other end of the
operating table is another subject, lost in his or hers. It is as though we are
thinking about two ashtrays of the same design sitting at either end of a
But now for the experiment itself. Our mad researcher begins by trading
one quarter of your brain for the corresponding quarter of the other. He
does this instantly, or through instantaneous freezing and thawing, so that
it does not register in the patterns of brain activity. What is the result?
Surely it would not be natural to think that you have gone over to the other
end of the table, along with a mere quarter of your material. Nor is it
inviting to think that either you or your experience is a quarter changed in
numerical identity. The natural thought is rather that you and the other
subject have remained wholly what - and wholly where - you would have
been if there had not been an exchange of quarters.
Next he exchanges a second quarter between your brain and the other's.
Now, it was wholly you, in the same position, after the first quarter
exchange, just as if it had never been done. So the second quarter must
merely be like the first all over again. There is again no change in what or
where you are. One thing to emphasize is that we may easily think of the
brains themselves in terms of fractions. Thus, though we might be a bit
puzzled about whether the brain that was originally yours is still the one
you've got after the second quarter exchange, if we like we can just fall
back on talking about there being half of the original brain with you and
half now over there with the other. But one could never talk about the
subject or his experience like that. So, anyway, what we should expect
after the exchange of second quarters is that each subject is still wholly
where it was at the start of the experiment.
You may guess what he does next. A third quarter exchange. And the
result must again be the same; you remain where you are. And a final
exchange, of fourth quarters, must also make no difference to where the
subjects are. But notice that this final result looks as though it should be
indistinguishable, except in history, from what would have been done if
the mad scientist had merely picked up the brains at the start and exchanged
their positions. All the material that was on the right is on the left and vice
versa. But if this had been done all at once we would have been sure to
say that the subjects as well as the brains had changed their positions.
The question is, could the difference in history that I have just indicated
as the only difference between the two procedures be enough to make for
the utterly different outcomes for numerical identity in the otherwise
indistinguishable results? It seemed to me very implausible that the dif-
ference in history could be enough. What suddenly struck me was that the
logic of experience was very different from what we normally supposed it
was. In fact, when we were thinking about a particular experience we were,
without realizing it, thinking about a type, a universal, rather than a token,
a proper particular or individual. What I ended in thinking was that, in an
experiment like ours, there had been numerically only one episode of
experience and only one subject from the beginning. There was, despite
the two brains at the two locations, but a single particular experience, as
of being precisely you, in just that spot where you seem now to be, reading
exactly like this, with all these current thoughts and sensations. And therein
there was but a single you. All these specific qualities of the experience
and its subject also determined the numerical identity. Experience and
subject occurred equally well, numerically the same, in either of these
realizations of them, in either brain. Therefore, at the end of either the
series of quarter exchanges or the immediate whole exchange, there was
no distinction of a subject on the right in contrast to a subject on the left.
No matter which way one did the exchange, there was throughout but one
subject - you - possessor of but a single experience.
Also, if you consider the physicalist account of personal identity so alluring, consider
these writings of Thomas Nagel:
consider everything that can be said about the world without employing any
reflexive expressions. This will include the description of all its physical
and their states, activities and attributes. It will also include a description
the persons in the world and their histories, memories, thoughts, sensations,
perceptions, intentions, and so forth. I can thus describe without
the entire world and everything that is happening in it - and this will include
description of Thomas Nagel and what he is thinking and feeling. But there seems
to remain one thing which I cannot say in this fashion - namely, which of the
various persons in the world / am. Even when everything that can be said in the
specified manner has been said, and the world has in a sense been completely
described, there seems to remain one fact which has not been expressed, and that
is the fact that I am Thomas Nagel. This is not, of course, the fact ordinarily
conveyed by those words, when they are used to inform someone else who the
speaker is - for that could easily be expressed otherwise. It is rather the
fact that /
am the subject of these experiences; this body is my body; the subject or
my world is this person, Thomas Nagel.
There is no physical fact that explains why of all the people in the world, you shall
only live the life of Brent Meeker. If there is no physical justification supporting
this fact, what is your motive for believing it?