Re: Is the Brain the Way?

From: HARNAD Stevan (
Date: Fri Mar 01 1996 - 20:41:58 GMT

> From: Dawson Jon <>
> Date: Fri, 1 Mar 1996 15:51:54 GMT
> computers work as our introspection does not how we do therefore by
> saying computers think in the same way we do, just because they can be
> caused to reproduce our actions is incorrect

Why do you say computers work the way our introspection does? How do
computers work? (And how do they match our introspections?) Or do you
mean computers DON'T work as our introspections do? How does our
introspection work?

Yes, some computers can "reproduce" our actions, and we know exactly how
they do that (by computation). We can "produce" our actions, but we have
no idea how. So if computation is the only working idea of HOW, how do
you know that idea is incorrect? Is it something you know about the way
WE do it? Is it something you know about the way computers do it?

Remember to give evidence and reasons, not just statements of beliefs of

> what is wrong with all lifeforms having a mind

Nothing wrong. Maybe they all do. Maybe they don't. Do you have any way
to tell? (Remember the other-minds problem? It gets harder and harder
to tell the more unlike us the organism or machine is.)

> -isn't having a mind a prerequisite to being a lifeform

Not as far as I know. Did anyone say so? How do they know?

> (and can you hence say that lifeforms
> have a mind and non lifeforms do not, but this is just really restating
> the problem, as 'humans' are lifeforms and machines are non lifeforms)

Correct; it's just restating the problem. Besides, we still don't know what
machines are, and aren't. We do have a pretty good idea what's alive and
what isn't. But you don't want to say everything that is not alive is a
machine, do you? Can you even say that everything that is a machine is
not alive? What is a machine? Substitute "X" for machine in all the
foregoing and you'll see how little it is possible to say that makes

> i find that phraseology presents a problem after all it has been said
> that the mind is made by cultural experience but it is impossible to
> undergo a MIND SHAPING cultural experience if you do not already have a
> mind

And that was already said too: Culture influences what's IN our minds,
but it doesn't "create" our minds. So forget about culture while you're
settling the question of what a machine is, and what does and doesn't
have a mind.

> if pinch/reflex indicates a presence of a mind then if you take someone
> who is lacking in the pain processing area of the brain are they
> lacking in a mind

This is a misunderstanding. Pain is just an example. Substitute any
experience at all for it. You don't need to have any PARTICULAR
experience to have a mind. You may be colour blind; you may have no
sense of pain. But you have to have SOME experience; you need to feel
something. Pain is just a very obvious example of something you feel,
one that we are all familiar with, and I suggested that when you think
of "having a mind," or "being conscious," you should use feeling pain as
your example.

A "reflex" is not relevant here; a reflex is not a feeling, it's a
behaviour -- an involuntary one. You can FEEL yourself performing a
reflex (if you're awake), and it feels as if you are doing something
involuntarily, like being pushed or pulled. If you find that a better
example of what it feels like to have a mind, use that...

> -can you not use your brain to overrule a reflex
> action and therefore is a pinch that creates no response more
> indicative of a mind because indicates the ability to
> experience,'think' and reformulate response based on data taken from a
> new experience

Unfortunately, this is missing the point. First, no, you cannot
"overrule" a reflex: Try not to move your knee when someone hits the
right spot under your kneecap! What you can overrule is a voluntary
behaviour. But that is irrelevant to the question of whether you choose
to use feeling pain or something else as you pet example of what it is
to have a mind...

> if when 'looking at the brain' during two different tasks the same area
> is activated during both, why does it mean that area is related to the
> problem? after all when cooking and writing an email my visual cortex
> is presumably active, but not involved in the problem solving
> experience any more than the fact that i can feel the onion or keyboard
> is

That is a good point! Use it in your essay on behaviour and brain

> how do we know which different bits of the brain do what if we cannot
> observe the stimulated area at the same time as we stimulate that
> area?

What do you mean "stimulate that area"? You mean direct electrical
stimulation? That's been done, for example, by Wilder Penfield, and by
George Ojemann. Stimulating parts of the temporal lobes is reported to
lead to vivid re-experiencing of long forgotten experiences.

> if by experiment we know what all different bits of the brain do, then
> where do we store our memories?

If by experiment we know what all bits of brain do, then by experiment
we can know which bits of brain store memories -- if memories are stored
in bits...

> (is it true that there is no evidence
> that our body contains an area for memory storage?)

No, the opposite is true. There are areas that, when damages, cause
various kinds of amnesia, perhaps including the permanent loss of
certain memories. But there is also evidence for distributed memory:
that many different "bits" are involved in "storing" memories. The
neuropsychology of memory is complicated, and no wonder, because no one
has a theory of memory that explains how anything could remember what we
remember. Such a theory would have to explain a lot more than just

> to go up to date, for our email coursework is it not true that mental
> imagery is a form of behaviour (debatable but if pupil dilation is
> then it must be),

No, the behaviour is what you DO. So if you are asked whether an X would
fall on or off an imaginary F that is superimposed on a grid, what you
are DOING, is looking at a grid with and X and answering (correctly or
incorrectly) whether the X would be on or off the F. THAT's your
behaviour. We can all observe that.

Now, while you are doing this, you might be aware of seeing an "F" in
your mind's eye, which feels very much like really seeing an F. That is
imagery, but only you can observe whether or not it is happening. That
is introspection.

What brain images can show is that while you SAY you are imagining an F
(and only you know whether that's really what's you're experiencing) the
same parts of your brain light up as when you are looking at an F. This
is what Kosslyn shows, as you will see in this week's reading about the
imagery debate.

That does not make imagery behaviour, but it does give some evidence
(doesn't it?) that something visual is going on when you say it is?
At least, it's the same kind of evidence that you are experiencing
something visual as when you are actually LOOKING at something, and
those parts of your brain light up (1) that are connected to your eyes,
and (2) that give rise to blindness if they are injured.

Go back and sort out what is observable behaviour, observable brain
activity, and unobservable (to anyone else) introspection in the above.

Now: is imagery behaviour, like pupillary dilation?

> and then asking us to base the answer to the question
> on "both behaviour and brain images" slightly misleading and would it
> not be better to say "what can we find out about the mind from brain
> images and other types of behaviour that we could not find out before
> we had the ability to brain scan"

You are perhaps mixing up the two senses if "images" being used here.
(They lead to cute but apparently confusing puns.)

(1) When you imagine something, when you picture something in your mind,
with your eyes closed, THAT'S imagery. It's not a behaviour; it is an

(2) Brain activity is observable, like behaviour. We can create colored
images that change colour depending on what you are doing
("macrobehaviour") and which part of your brain is active at the time
("microbehaviour"?). THAT is what I mean by "brain imaging."

Don't confuse mental imagery with brain images. The essay question was
about brain images. The mental imagery topic is next week.

> also this then means that saying
> "that we could not find out using behaviour alone" does not work
> because behaviour on its own still includes mental imagery

No. The behaviour is what everyone can observe. Only YOU can observe
what you imagine. I cannot observe whether or not you are imagining a
pink elephant. However, I CAN see a part of your brain light up every
time you SAY you are imagining a pink elephant. Or whenever you add 2 +
2. Those brain images, which accompany behaviour, and also accompany
introspection, are the brain images you need to consider when you
discuss how they can reveal things that are not revealed by behaviour

> (the original question was "what can we find out about the mind by
> observing both behaviour and brain images that we could not find out
> using behaviour alone")

And that still IS the question. It is brain images, of the kind I was
describing today, derived from EEGs, ERPs, PET Scans and MRI's that this
is about. Read Posner & Raichle.

How do brain images tell as things that studies on behaviour alone
(including the "chronometric" studies, measuring reaction times using
Donders's subtractive method) cannot tell us?

Behaviour is observable. Brain images are observable. Mental imagery is
not behaviour, and it is not observable (and not what the question is

> finally is it possible that mentioning of other peoples articles, that
> they have already sent to the list, be only copied and repeated if
> actually essential to the quoter, when expressing the point

Yes, it is a good idea, and will save us all a lot of time and disk
space, if you quote only the parts of the text that you are commenting
on. Delete the rest.

In this case, though, as you see, I commented on every word...


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