X-Message-Number: 3754
From: (Joseph J. Strout)
Newsgroups: sci.cryonics
Subject: Re: swapping etc
Date: 26 Jan 1995 04:49:43 GMT
Message-ID: <>
References: <3g2j47$>
In article <3g2j47$>, Robert Ettinger
() made a very helpful attempt to clarify the "self
circuit"...
> The ESSENTIAL part or aspect of a person (or anything with LAWKI,
> life-as-we-know-it) is FEELING, qualia, the subjective condition, the
> capacity to feel pleasure and pain etc. Barring dualism or mysticism, it must
> be a physical part or aspect of the brain or its functions.
> It may be distributed; it may require time-binding; possibly it cannot exist
> in isolation from its support mechanisms and interfaces; we know so little
> about it in objective terms that many scientists will not even admit it as a
> concept or subject for study. But the incontrovertible fact is that that we
> have subjective lives, and this is our essence.
Thank you, this does indeed clear things up a bit. I wouldn't say it's
completely closed to modern science, however. There have been a number
of studies of the so-called "pleasure centers" of the brain. I prefer
to speak in terms of drive states, motivation, and reinforcement, but
it's the same thing. Particularly important structures for this are in
the hypothalamus (esp. the medial forebrain bundle) and the nucleus
accumbens. More generally, the limbic system (a loosely defined set of
deep structures in the brain, almost circling the corpus callosum) seems
to be heavily involved in emotional states, as well as the physiological
changes that accompany emotional states. These include anger, fear,
sexual behavior, and probably more subtle emotions which are difficult
to test in the lab. There's still much research to be done, but we are
not wholly ignorant. For the time being, I will (tentatively!) think of
the self circuit as the limbic system.
> The (isolated) self circuit doesn't know, understand or care whether it is
> the "same" as before; it is (to some extent) just a sounding board, a
> resonator or semihomeostatic circuit that has a life of its own but is not
> free-standing. By itself, it has no intellect, just raw feeling. The self
> circuit is the most essential part of a person, but the WHOLE person is the
> integration of the self circuit and the associated memories and habit
> patterns etc.
This is a very sensible position. The point of my previous post was, in
short, that I can imagine no reason to swap only part of the brain. I'm
afraid I confused the issue, though:
> Dr. Strout's posting seems to mix and confuse "swapping" with "uploading." I
> have commented on "swapping" above--transfer of tissue (or organization of
> tissue) between two brains.
You're right; I often jump back and forth because I see them as
philosophically the same issue. Speaking in terms of transferring
tissue eliminates the question of whether uploading is possible, while
still enabling many of the same personal identity problems.
> Uploading--transferring a persona into some kind
> of computer--is in some ways easier to deal with, because there is no reason
> in principle to think it can be done. For those who still don't get it, once
> more very briefly the reason: You can't necessarily realize an arbitrary
> device in an arbitrary medium.
Here's the first place where we really disagree: I would say there is no
reason in principle to think it CAN'T be done. There's nothing magical
about neurons; they are complex devices, but devices nonetheless. I am
currently working at the Computational Neurobiology Lab at the Salk
Institute, where neurons are routinely modelled in fair detail. The
simulations are crude but improving; already they exhibit many details
of the dynamics found in real neurons. If we can simulate a single
neuron accurately, then (in principle) we can simulate a network of
them. If a brain is reconstructed neuron for neuron, each one
performing exactly like its original counterpart, then we have realized
the brain device in electronic (or optical, or whatever) media. [Of
course, there are myriad messy details involved with interfacing with
the real world, but I think those can be granted if the rest of the
brain works.] This is what I mean by "full brain upload": copying every
neuron in the brain.
Now, if "upload" makes you think of configuring some sort of symbolic,
algorithmic program on something like today's sequential computers, then
I share your skepticism completely. But I imagine a much closer
replication, implemented in specialized hardware.
> Since we don't yet know the physical features that characterize the self
> circuit, it is not yet possible to say whether it could be duplicated outside
> of organic matter.
This I do not understand. What features could possibly be unrealizable
outside of organic matter? Quantum effects? -- we use quantum dots.
Hormones? -- we duplicate their effects through software. Learning? --
we use self-modifying hardware (or software). I mean no sarcasm; I
simply don't have a grasp of what you have in mind here. And I don't
mean to imply that it would be easy; on the contrary, it's a truly
Herculean task. But what theoretical obstacles are there?
> If "full brain upload" does not mean atom-by-atom replication/correction,
> then "simply" uploading the entire brain could only mean transplanting the
> entire brain. In that case the result is easily understood: Jim has acquired
> Joe's body, which would be awkward in many ways but not disturbing on a deep
> philosophical level.
Not atom-by-atom, but neuron-by-neuron, which I think is close enough
for the philosophical conclusion to remain valid.
--
Joseph J. Strout Dept. of Neuroscience
Univ of CA, San Diego
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