Philosopher of the Month - Descartes & the mind-body problem

simu

Mind-Body Problem: Descartes' dualism and refutations

In this thread, it was decided that Descartes' views on the mind-body problem would be a good subject for the first "Philosopher of the Month" thread. So here goes...

The idea of the mind and the body being separate entities wasn't new in Descartes' time but he's considered to have been the first to approach this subject in a systematic manner, his work has had great influence on subsequent thinkers and the mind-body problem has not been resolved in a satisfactory manner to this day. This should make for some interesting discussion!

So here's the first list of articles for this thread - the idea is that everybody who participates in the thread will have read these and be familiar with them (don't worry - it's pretty short):

(1.) List of articles to read before taking part in this thread:

By Descartes himself:

MEDITATION II OF THE NATURE OF THE HUMAN MIND; AND THAT IT IS MORE EASILY KNOWN THAN THE BODY

MEDITATION VI OF THE EXISTENCE OF MATERIAL THINGS, AND OF THE REAL DISTINCTION BETWEEN THE MIND AND BODY OF MAN

(2.) Articles with counter arguments/other approaches to resolving this problem
Everyone should become familiar with at least two refutations/different approaches to this problem, more if you have the time. I've tried to give a brief description of the contents of each here so that you can pick the ones that interest you most.

Responses to Descartes in the 17th century

Responses to Descartes in the 18th century

Responses to Descartes in the 19th century

An interview (in two parts) with Daniel Dennett, a contemporary philosopher working on the mind/body problem - he rejects the Cartesian distinction between mind and body & is interested in artificial intelligence:
Part One]
Part Two

Another rejection of Descartes' dualism, Wittgenstein argues that Descartes was "tricked" into dualism by the structure of language:
Wittgenstein sans The Private Language Argument

Yet more refutations of Descartes' ideas: an article about the responses of Ryle and Merleau-Ponty:
Go here, then copy the following text and add it to the URL to download the article: /Challenging%20Dualism%20I.doc

John Searle - he rejects the contemporary idea that mind is to brain what program is to computer:
Click here first, then scroll all the way down to the article entitled "Searle, John - Minds and Brains without Programs (1987).doc" and click!

Heidegger's Take on Descartes - quoting from the article abstract:” Starting with Descartes, the subject is a thinking thing that is not extended, and the object is an extended thing which does not think. Heidegger rejects this distinction between subject and object by arguing that there is no subject distinct from the external world of things because Dasein is essentially Being-in-the-world." :
Heidegger's Reading of Descartes' Dualism: The Relation of Subject and Object

(3.) Other related articles and web pages

If you want to read all of the Meditations, they're to be found here:
Meditations on First Philosophy

Very brief account of Descartes' life and the significance of his writings.
RENÉ DESCARTES AND THE LEGACY OF MIND/BODY DUALISM

An interesting article about the influence of Descartes on medical practice:
CARTESIAN DUALISM AND THE CONCEPT OF MEDICAL PLACEBOS
Chart showing the different properties of Mind and Body, according to Descartes:
Descartes' Mind/Body Dualism

Review of Descartes' ideas - Abstract: Rene Descartes' view of dualistic interactionism is reviewed, and factors leading to its rejection are explored.
Cartesian Dualism: Mind and Brain Interaction

A summary of the Meditations. These might be helpful if you're having problems understanding something but you should read the texts themselves too.
Descartes’ Meditations 1 to 3
Meditations 4-6

Notes
Anybody who mentions ideas that are not explained in category (1.) above will be expected to give a brief explanation of them if it is thought that they will not be familiar to all participants. This should be done inside the thread if possible rather than just giving links - explain in your own words or paste short excerpts from other sites(don't forget to give credit for these).

List (2.) is certainly not exhaustive - if you find other articles that you think would enhance it, PM me and I'll add them to the list. At least, I hope people find enough variety and counter-arguments to Descartes there to start off with!

As to how exactly we're going to discuss this here on boards, I don't want to dictate which approach to take and this is the first time such a thread as this has been done here so I really don't know what to expect! Some suggestions off the top of my head: When you're reading, pay close attention to the texts and examine the way the writer goes from one proposition to the next. Do you find any flaws or unexplained directions in their reasoning? Can you think of possible objections to claims they make?

With Descartes, do you agree with everything he says or do you find some or all of what he writes unconvincing? Which parts and why? Do later critics of Descartes address these issues? Do they come up with more convincing answers? What's your own take on the mind-body problem? With respect to other posters, do you agree with their interpretations of the texts or with any objections they raise or with their views on the mind-body problem? If not, be ready to argue your own point of view! ... ...

simu

This thread has been up for a while now! So, rather than launch into a long post about my own views on Descartes and all (and risk having this turn into the "Simu discussing the mind-body problem with.... err... herself" section of boards!), I'm wondering if anyone else has been taking a look at some of the articles I linked to in the initial post! Any reactions to the Descartes texts? Or even any bits you find unclear and would like to try and figure out the meaning of by discussing here? ....

And, to get things going, some pretty blunt questions:

What is the mind?
Is the mind seperate from the body? If so, what's the connection between the two (if any)?
Do you think humans will ever make computers that have consciousness? ... ....

keu

great questions...I've been waiting for some interesting answers.
(I thought if I replied it would only act as a base for denigration, so I've been waiting for someone else to throw the dice.)
but since no one has even entered the arena, I was wondering Simu, if you were to continue talking to yourself (bearing in mind the topic of conversation)...who exactly would you be holding a conversation with?

simu

but since no one has even entered the arena, I was wondering Simu, if you were to continue talking to yourself (bearing in mind the topic of conversation)...who exactly would you be holding a conversation with?

Well, myself - I wonder to myself if I did write the other posts attributed to simu and if I'm doubting that, I must exist (according to Descartes)... ... work the rest out yourself! Unless an evil demon type is decieving you (remote viewer) and manipulating your senses so that you think wrongly that I exist!:)

Actually, that got me thinking about Descartes' position on memory. In Med. 2, he says that it's unreliable "I believe that none of those objects which my fallacious
memory represents ever existed" (Meditation 2, 2nd paragraph) So, wouldn't this affect the whole cogito (the "I think therefore i am" argument). At one instant, he's doubting something, the next instant, he's thinking about the fact that he was doubting. But, isn't he relying on his memory here and could his memories not be false? And what if the rules of deduction he uses are false??? (OK, so maybe there's a benevolent God that makes things in such a way that memory, while fallible, used in conjunction with reasoning, generally leads humans towards truth and understanding rather than towards obscurity but his proofs for God don't come until after he has proved that he exists himself...)

I have a clear and distinct idea of myself, in as far as I am only a thinking
and unextended thing, and as, on the other hand, I possess a
distinct idea of body, in as far as it is only an extended and
unthinking thing, it is certain that I [that is, my mind, by which I
am what I am] is entirely and truly distinct from my body, and may
exist without it.

(from the 6th Meditation)

To me his definition of himself as a "thinking thing" seems a bit vague, and circular - a thinking thing is a thing that thinks. (OK, he goes into more detail about what thinking is - but it still boils down to thinking). And how "clear and distinct" can a person's knowledge of their own mind be? To me, it seems not very "clear and distinct" at all. (But then again, I'm influenced by the idea of the subconscious that wasn't there in Descartes' time!) How can you know for sure that this thinking thing isn't extended (i.e. does not take up space)?

And, there's the whole problem of links between the mind and the body if the two actually are distinct. Descartes dosen't really go into this - but some of the explanations later people came up with to account for dualism were, to me, well a bit messy and contrived...

... but this post is getting long enough already without going into that. So, what do ppl here think? (Feel free to rip my ideas to shreds if you want - just because I'm moderator of this forum doesn't mean I can't make mistakes:))

keu

Unless an evil demon type is decieving you (remote viewer) and manipulating your senses so that you think wrongly that I exist!

good stuff
Lady I have a hard enough time keeping these answers within the philosophy frame as it is lmao.

At one instant, he's doubting something, the next instant, he's thinking about the fact that he was doubting.

I thought that this was how descartes came up with his "I think therefore I am"
First he tried to prove that he didn't exist, by doubting his existance, he was able to prove that he actually did exist. He couldn't prove he didn't exist, (because he could think that thought) and therefore because he thinks..he is...
or at least thats my perception.
I am I exist.

(But then again, I'm influenced by the idea of the subconscious that wasn't there in Descartes' time!) How can you know for sure that this thinking thing isn't extended (i.e. does not take up space)?

I have a similar opinion. I do consider that, thought; (even before it's thought if thats possible) as something similar to anti matter.
I don't want to dig up the past, but in my original post about the big bang, I was trying to systemize the essence of all that is, very difficult task.
but the reason I tried, is so that when comments like this arrive....

(OK, so maybe there's a benevolent God that makes things in such a way that memory, while fallible, used in conjunction with reasoning, generally leads humans towards truth and understanding rather than towards obscurity but his proofs for God don't come until after he has proved that he exists himself...)

....I can utilise this system to provide an answer. LOL

ie: IF I had the essence of a singularity, than I am matter and anti matter (a bit like body and soul) then who is to say that there is not a greater extension of myself (thought) which takes up space? (and not percievable outside the realms of thought)

Descartes had a very similar idea in his pursuit to put in place a system by which all knowledge could be gathered in a single and complete science.

Just to quote from a little piece I have in a book here:

"he also regarded the human body as subject to the same mechanical laws as all matter, distinguished only by the mind which operated as a distinct, seperate entity."

anti matter?

Fysh

Very much off-topic here....but Anti-matter and matter are subject to the same physical laws - antimatter is simply a term for those particles whose qualities are symetrically paired to what we normally think of as matter (as in, we think of electrons as part of matter, and therefore positrons are antimatter - positrons are the same as electrons except they have a positive charge).

Anti matter and matter interact destructively, leaving gamma radiation. Therefore if the soul was made of antimatter, it could not be linked in any way to the body.

Back on topic - There's an interesting article relating to this topic are over here. There was also something in this weeks issue about where thoughts originate, but it's not on the site - when I check it at home I'll edit this post to add it - it's basically to do with how choices are "made" in the brain before the conscious awareness of making the choice is experienced.

Fysh

What I meant was, if the soul has a material existence comparable to that of our bodies and it were comprised of antimatter, then a physical bond between the soul and the body would lead to a destructive interaction in which both matter and antimatterare converted to gamma radiation.

There's a couple of caveats on this, however:

1)the matter and antimatter must be of matching types - for example, while positrons and electrons will annihilate each other, positrons and antiprotons will not do so (in fact, positrons and antiprotons interact in the same way as electrons and protons do).

2)if the bond were a quantum bond, then this destructive interaction would not necessarily occur. However, having massive bodies (even if its mass is only of the order of grams) would make this quantum bond *very* complicated in terms of mathematical descriptions and, well, one of the rules of thumb when trying to use quantum theory is that when you're looking at the macroscopic view of the world, classical physics tends to apply. Ie given the number of particles involved in something weighing 5g and a given human body, it's likely at least two particles will interact. Whether or not they are matching types is another story, however.

That said, I don't see any simple way in which the soul or the mind can be explained using antimatter...

keu

back to the original point

can the consciousness exist without a body?
I determined that all my thoughts were in essence not physical, yet they exist.
In order for anything to exist, it must be something and I'm trying to figure out what that something is. When Des sat down and thought about this motivational source of being he called this part of himself the soul and defined the soul as....

...and all those actions I referred to the soul; but what the soul itself was I either did not stay to consider, or, if I did, I imagined that it was something extremely rare and subtile, like wind, or flame, or ether, spread through my grosser parts."

I'm stuck on ether, of which the dictionary definition is:"Physics. An all-pervading, infinitely elastic, massless medium formerly postulated as the medium of propagation of electromagnetic waves."

Now..I just got to get my Science-for-the-inattentive-and-brainless-layman book out and figure out exaclty how electromagnetism works.

simu

I have a similar opinion. I do consider that, thought; (even before it's thought if thats possible) as something similar to anti matter.
I don't want to dig up the past, but in my original post about the big bang, I was trying to systemize the essence of all that is, very difficult task.
but the reason I tried, is so that when comments like this arrive....

This anti-matter stuff makes no sense what so ever but I think Fysh has already explained that. What I am questioning is Descartes' statement that he knows his own consciousness.

I'm stuck on ether, of which the dictionary definition is:"Physics. An all-pervading, infinitely elastic, massless medium formerly postulated as the medium of propagation of electromagnetic waves."

Er, read that more carefully - the idea has now been discarded by physicists.

...and all those actions I referred to the soul; but what the soul itself was I either did not stay to consider, or, if I did, I imagined that it was something extremely rare and subtile, like wind, or flame, or ether, spread through my grosser parts."

Afair, he is talking here about his beliefs before he started his method of doubting everything, he's just using ether, flame etc as metaphors.

Fysh

Electromagnetism as a theory is still currently accepted - but the ether theory was discarded once Special Relativity was accepted as a theory. The ether was really just a way of explaining certain phenomena which otherwise made no sense.

Regarding anti-matter - while I can't cite any specific research on the subject, I'm doubtful that antimatter is present to any extent in any area of the brain, since if there were significant amounts of it it would likely have interfered with particle physics experiments, but more importantly result in serious brain tumours (gamma radiation is generally considered the most hazardous form of radiation). On the current facts, it's very unlikely that anti-matter is present in the brain. In the quantum link case, the maths governing the possible states of that amount of antimatter in the vicinity of matter would be very complex, but the behaviour would tend towards the "classical physics" view - they interact and destroy each other.

I have no idea what the whole metaphor thing is about; I certainly don't agree that philosophy is metaphorical in nature. It is the search for truth by deductive reasoning; obviously each individual must question that, but in maths and physics among many others, many proofs have been constructed which have stood up to attempts to discredit them for centuries. We don't need to know if the mind is independent of the body in order to exercise the mind. If it were to turn out that the mind is the result of extremely complex neural interactions within the brain (and therefore inextricably linked to the body) would that detract from the thoughts of that mind? Surely not. The main implication of such a scenario would be that we could better understand the limitations of our ways of thinking, in the same way that analysing the electronic circuits that make up a computer will help us understand the limits of what sort of calculations it can perform.

Now that we're back to the mind-body problem...I find it interesting that Descartes at one moment states that he doubts everything his senses have to tell him, but then decides to trust his memory of having those doubtful thoughts sufficiently to conclude he exists. This seems contradictory to me, but the alternative is a situation where we can only trust our thoughts as they occur to us - and if, as a brief piece in the current New Scientist suggests (unfortunately not available online), our thoughts may originate in the brain before we become consciously aware of them, even this may not be enough. At best we would need a better understanding of time in order to know how to pinpoint when we were having a particular thought; at worst we simply cannot trust anything not to be an illusion and must simply make our way through the world knowing this.

Manchegan

Originally posted by Fysh
At best we would need a better understanding of time in order to know how to pinpoint when we were having a particular thought; at worst we simply cannot trust anything not to be an illusion and must simply make our way through the world knowing this.

Any number of experiments have shown that our perception inevitably clouds what we would accept as *real* to the extreme where it is reasonable to doubt the *reality* of our perception. What is *real* to us is only the salient attributes of the object as it applies to us: we have a generally accepted concept of "wall", for instance, but if I were a bat, I would undoubtedly have the same concept of "wall" as a human - a vertical obstacle of appreciable breadth - but this would extend to include "cliff", "window" etc., i.e. the distinctions a human makes between "wall", "cliff" and "window" are irrelevant to me.

Neither should the genesis of a thought distract from the discussion of thought itself - it could possibly be demonstrated that the timeline preceding the conscious awareness of a thought could be the accumulation and evaluation of data coming from our senses. If I think "orange", it could be the culmination of the thoughts/evaluations/classifications of atomic *thoughts*, "If round AND orange AND soft THEN orange", the "round" evaluation being the culmination of the thought/evaluation/classification of perspective and depth of individual visual sensations, each such evaluation being an atomic *thought* in its own right.

It might be useful to consider the example of someone who doesn't "think", who only "senses", the character Funes in JL Borges' Funes the Memorious:

He remembered the shapes of the clouds in the south at dawn on the 30th of April of 1882, and he could compare them in his recollection with the marbled grain in the design of a leather-bound book which he had seen only once, and with the lines in the spray which an oar raised in the Rio Negro on the eve of the battle of the Quebracho.

It was not only difficult for him to understand that the generic term dog embraced so many unlike specimens of differing sizes and different forms; he was disturbed by the fact that a dog at three-fourteen (seen in profile) should have the same name as the dog at three-fifteen (seen from the front).

Without effort, he had learned English, French, Portuguese, Latin. I suspect, nevertheless, that he was not very capable of thought. To think is to forget a difference, to generalize, to abstract. In the overly replete world of Funes there were nothing but details, almost contiguous details.

Could such a person exist?

EDIT: Or rather, could it be said that Funes "lost his mind"?

simu

Once you start to doubt everything, it's impossible to find anything certain, as far as I can see. As I said, I don't think Descartes manages to achieve his aim of finding one certain thing from which to start his reasonings.

The best answer I've seen to combat this sort of scepticism is that there's no particular reason to believe that it is better to doubt everything than not to do so.

someone who doesn't "think", who only "senses",

That's interesting. As for the learning to speak languages thing, I was reading recently about people with extremely low IQs who can talk extremely loquaciously and creatively. It's called Williams Syndrome.

Anyway, where do people stand on the mind-body thing? Are they both aspects of the same thing? Or are they separate yet connected in someway?
I actually posted a list of appraoches to the problem in this thread if that's of any use.

Manchegan

Originally posted by simu
Once you start to doubt everything, it's impossible to find anything certain, as far as I can see.

It is perfectly reasonable, indeed rational, to doubt what your senses tell you. After all, unless we are the same as Funes, they are merely approximations of objective reality.

Take, for example, the case of the superstitious pigeons.

The behaviorist psychologist B.F. Skinner placed a series of hungry pigeons in a cage attached to an automatic mechanism that delivered food to the pigeon "at regular intervals with no reference whatsoever to the bird's behavior". He discovered that the pigeons associated the delivery of the food with whatever chance actions they had been performing as it was delivered, and that they continued to perform the same actions:

"One bird was conditioned to turn counter-clockwise about the cage, making two or three turns between reinforcements. Another repeatedly thrust its head into one of the upper corners of the cage. A third developed a 'tossing' response, as if placing its head beneath an invisible bar and lifting it repeatedly. Two birds developed a pendulum motion of the head and body, in which the head was extended forward and swung from right to left with a sharp movement followed by a somewhat slower return."

But they are just pigeons, you say. But then, doesn't light travel in a straight line? Doesn't the earth appear flat? etc. etc. Until and unless such illusions encroach upon your ability to cope with your environment* you'll happily accommodate them, gloss over them, block them out, approximate.

As I said, I don't think Descartes manages to achieve his aim of finding one certain thing from which to start his reasonings.

He can, however, claim - validly - to be equally certain of the reality his self-consciousness as he is uncertain of the reality of the world as presented to him by his senses.

The best answer I've seen to combat this sort of scepticism is that there's no particular reason to believe that it is better to doubt everything than not to do so.

That begs the question somewhat - is your illusion any better than my doubt?

EDIT: * for example, the food stops being dispensed no matter how much I nod my head, turn clockwise etc., or I need to find an alternate route to the Indes, or determine the exact position of a star.

simu

It is perfectly reasonable, indeed rational, to doubt what your senses tell you. After all, unless we are the same as Funes, they are merely approximations of objective reality.

I agree. But I don't think you can stop at your senses either - you could also doubt your ability to reason from the material your senses provide you with, you could doubt the validity of logical propositions, you could doubt the scientific method and so on.

The best answer I've seen to combat this sort of scepticism is that there's no particular reason to believe that it is better to doubt everything than not to do so.

I should have said it was the best answer I've seen from an even less convincing lot! Yet, philosophers do go on to build theories about existence despite this scepticism - if they were to stick with scepticism, all they could say would be that knowledge is impossible.

Manchegan

Originally posted by simu
But I don't think you can stop at your senses either - you could also doubt your ability to reason from the material your senses provide you with, you could doubt the validity of logical propositions, you could doubt the scientific method and so on.

Don't worry - I'm not looking to tear down your Cathedral of Knowledge All I ask is that you vouch for it with more humility. After all, until we needed to correctly predict the date of the Vernal Equinox, it was a logical proposition that the sun and planets moved around the earth on crystal spheres making music as they went. A hundred years ago ether was a logical proposition and cocaine in solution was sold over the counter as a "pick-me-up". Remember that mathematicians suggest that it is best to conceptualise the universe as having 11-or-so dimensions. While to survive and thrive we have found no more than four necessary (although it could go some way to alleviating the shortage in housing and traffic congestion ), if it became necessary to discriminate on this basis, life now compared to then would be regarded as so much nodding of the head, turning clockwise etc.

That said and after all, isn't my proposition logical and valid, my doubts notwithstanding?

I should have said it was the best answer I've seen from an even less convincing lot! Yet, philosophers do go on to build theories about existence despite this scepticism - if they were to stick with scepticism, all they could say would be that knowledge is impossible.

Yes, knowledge is impossible without categorisation, generalisation, interpretation etc. Anyone looking at the streams of ones and zeros a computer permutes will tell you that. Mathematics wouldn't get far if, holding an orange in one hand and an apple in the other, we couldn't agree that I had "one" of each, no matter the dissimilarities between the two. Funes, if he existed, wouldn't last long as he'd be run over as soon as he stepped outside, being unable to conceptualise the general idea of "car".

I said "somewhat", however, because the advice you received was right but for the wrong reason. Your Honour, the Defence calls on Watanabe's Ugly Duckling theorem (the link is where I started to think of Funes as it applied to this question) - and theorem means it's been proven mathematically (link - search for "watanabe" - and for you wags out there, yes I'm aware of the irony of basing my argument on a system I claim to be arbitrary ). Simply put, there is no way to say some things are more similar than others, so any such distinction is essentially arbitrary. From this it follows that, although we've seen that it is essential to choose, categorise or overlook differences, those decisions are only "good" or "bad" (read "logical or illogical") depending on how best they enable me to survive and thrive in my environment. The concepts "1" and "zero" etc. persist for just this reason etc..

Similarly, although Descartes himself wouldn't because of human snobbery, I'd ascribe the same process to the other descendants of the primordial goo - my friend the bat and the ivy plant on my table - even though they interpreted their environment differently to me, just as my choice to be a programmer can't be judged qualitatively different from my friend's to be an accountant, other than on the criterion that our livelihood is supported by that choice. As fundamentally arbitrary decisions, however, they must remain subject to re-evaluation based on circumstance, be it the KT event, a recession or any other paradigm shift (viz. the celestial spheres).

At this stage, at last, I'll attempt to draw the discussion back from the tangent it is on back on-topic. My success or otherwise will determine if simu is entitled to open up a can of whoop-ass on me for derailing it in the first place.

Leaving aside the fact that we commonly accept a certain level of mind-body duality (someone in a chronic vegetative state, while living, is no longer considered to be alive), the problem I have with the mind-body problem is that it isn't a problem, it's an answer. The question, therefore, is "what's the question?" The answer to that is the question "what is life? What does it mean to be alive?", a question that goes further back than Descartes, back to Plato and Aristotle, centering around the nature of anima, the "breath of life". The first proper treatment of anima comes from Aristotle, and it is important to remember that in using the word he refers to it as a quality, like "green", rather than an object (viz The soul is thus the lowest, first stage of actualization of the body that potentially has life. "If the eye were an animal, its vision would be its soul.").

Anima, under this definition, is just that interpreting, approximating, "thinking" quality possessed of all living things I was discussing, just as an inanimate body cannot interpret its environment and therefore is not. Strictly speaking, therefore, it is correct to assert "I think, therefore I am", given latitude on the interpretation of "think" and "I".

Descartes' answer, although a screwball that skewed the debate in the succeeding centuries, was logical if extreme in the context of the debate as it reached him, as a millenium of medieval thought had narrowed the scope of the term to its applying only to humans (Descartes himself considered dogs to be soulless automata, for instance) and pertaining specifically to the immortal soul (an interesting aside is the fact that the theology of the soul has arisen without the word appearing once in the Bible, or so I'm told). The extent of the effect this had can be seen in the fact that Jung appropriated the term like a second-hand car for one of his own concepts. To reinstate living things to possessing anima, although not exonerating wackier aspect of his conclusion, at least would give it some qualification for being reasonable.

Unfortunately, Descartes has led us down the philosophical dead-end of the "ghost in the machine" debate. Asking "is the mind a machine?" or "can a machine be made to model the mind?" is to miss the point and is ultimately as futile as asking "can we make a mechanical banana?". Accepted, a machine could feasibly recreate a Bach partita, but it could only aspire to mimicry, as the impetus to create music is an inherently human trait. When Johnny Snake, of the legendary Snakes of Desire, fresh from their Schnitzel und Tinsel Tour 2003, gets up on stage and announces "Und now a word from our sponsors..." before launching into a rendition of the tune to the ad for 80s chocolate bar "5-4-3-2-1", and you ask me "can a machine do that?" I'd say "no problem". But it would be too much for a machine to come up with an idea that would inspire the same emotions of empathy, nostalgia and sheer fun as that, as to do so would require the recreation of the environment that gave rise to it as well as a machine that would respond to it in the same way. And anyway - we already have Johnny.

As to whether a machine could think according to its own nature and in response to the environment it is in, and therefore fulfill the criterion of being alive, that would seem to me to be more feasible, if, as yet, unproven. Right now, all we're doing is hard-coding our own preconceptions.

simu

The best answer I've seen to combat this sort of scepticism is that there's no particular reason to believe that it is better to doubt everything than not to do so.

(simu)

So, modifying the above somewhat, it's more practical to start building categories that help us survive in and understand the world than just wailing about the impossibility of knowledge, but yet, always keeping in mind that our categorisations are arbitrary and may need to be modfied as new things present themselves to us.

(And whilst all of this - our categories, the way our minds do the categorising, the things the categories are based on, our minds - could be the creation of some being manipulating all our senses, we have no way of knowing about this (unless that being messes up its "programming work"!) and so it is irrelevant - in fact, if you reject Descartes' mind/body split, the being most likely wouldn't be manipulating a mind that had come from somewhere else - the being would have created the mind bit of us along with the rest of us - like The Über Sims!).

I'm still not convinced that Descartes escapes uncertainty on his own terms though - he was after one absolute thing on which to found his philosophy rather than a useful if arbitrary and possibly erroneous base.

That said and after all, isn't my proposition logical and valid, my doubts notwithstanding?

(Manchegan)

Well, I would say that it is a reasonable modus operandi to adopt in our present situation. (where reasonable = appears most likely to provide results that help us to approach a solution).

Unfortunately, Descartes has led us down the philosophical dead-end of the "ghost in the machine" debate. Asking "is the mind a machine?" or "can a machine be made to model the mind?" is to miss the point and is ultimately as futile as asking "can we make a mechanical banana?".

(Manchegan)

Well, I'd say that body and mind together is a machine, but a machine that can only be understood on its own terms - there's nothing else that we can compare it to. The Turing test is fun but I imagine that if we did meet an alien consciousness that had evolved separately from us humans (or a machine that had developed "true" consciousness i.e. on its own terms rather than simulating humans), it would fail the Turing test - it might be impossible for us ever to understand and communicate with it, all the more so on the intuitive level humans communicate with each other. Whilst attempting to create "human emulators" will probably have some practical benefits for us, I think that the idea of creating a program that passes the Turing test will, at some point, seems as irrelevant and amusingly eccentric as the 19th century hope of creating mechanical dolls that could pass as humans.