h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

In sentence 1 those who do not shave themselves may or may not be shaved by Harry. In sentence 2 they must be.

Extension of the halting problem: a predicting machine may not predict its own future internal states. (Discuss with reasons)

I think the same would apply (for the same reasons) to a consciousness machine trying to be conscious of its own internal workings.

Noggin

Cool! Will have a look for him! Thanks! What did you think of my journal entry?

Will reply to Nog in a mo...but inanother post!

i always wondered about machines and artificial intelligence: if a machine had 'consciousness' under the Turing test, is it really conscious?

So far so good, Nog. Would you care to also comment on the shaven or not state of the punters and, in particular, Harry. I think these are the most unexpected consequences of this little conundrum.

I noticed the other stuff on that page but didn't look at it. Gonna haft now

With a sufficiently sophisticated manual, Searle in his Chinese room would pass the Turing test. To be fair to Turing, it's a test for humanity I think, not consciousness (don't quite know what the diff might be in real terms though). I think that a fly is more conscious than any artificially intelligent machine that we can currently devise.

I'd send you my response, but not before Nog has played with the thing some more. It would be interesting to see whether we agree since this particular form of the problem was new to me.

This will come as a disappointment, but you have to do the thinking! There is no substitute, and in the end it's fun and easier than the alternative. I can let you have some easier tasks to solve if you need practice.

I know I have to think occassionally but it hurts so much!

I suppose I'm being lazy at the moment: but logic is not my forte shall we say [I've never been what you call logical ]

FwT

I have quite a low pain threshold myself, so I would never advise doing anything that might hurt! On the other hand, thinking can be fun. Was Buridan's ass lazy, logical or subject to choosing on a more emotional basis? Whichever way, he expired! Do you know the story?

The ass found himself exactly midway between two equally delicious bales of hay. There were no grounds whatsoever on which to base a choice of one rather than the other, so the poor, confused creature starved to death.

I've heard that story before, but in a different guise: a dog is equidistant to two piles of food: if one is bigger it will go to the largest...however if they are equal in weight...it will starve deciding which one to go to

It wasnt logic or laziness or emotions that dictated the decision, because no decision was ever made...that was the problem!

How do I know YOU are conscious? (I don't mean here that you may be a program in h2g2's server - I'm thinking of face to face interactions.)

The fact of the matter is we instinctively respond to other people on the basis that they are conscious, and that when they talk about consciousness they're talking about the same thing we are. We don't respond to computers in this way and to date they don't respond to us in that way either.

Noggin

While you're about in the quad, Noggin, do you plan to add to your reply to the 'Harry shaving' question? If not, I'll post my response for FwT.

Cogito ergo sum: that's how I know! PLus, we define consciousness: there is no independent value, so we have defined in such a way that we are included...

I like your linguistic argument for 'other minds' FwT. It's the one I prefer too. I find Wittgenstein's 'private language' argument a struggle at the best of times, but if he's right we couldn't have the concept of consciousness were it not something to which we all have access. Your definitional way of putting it is more comprehensible even if it does skip the question of quite how we manage to define 'consciousness' to our mutual satisfaction.

Your blithe use of the 'cogito' is a bit suspect FwT. Descartes' use of the word 'cogito' - 'I think' really does beg the question of whether there is an I to do the thinking. He should really say 'There is a thought, therefore I am' but that doesn't work, does it? How does he know that the thought is his? Alternatively, the cogito is shorthand for "There is a limited scope of awareness of things, that can't be doubted, and whatever has this particular set of awarenesses shall be called 'I'".

OK. Enough time for other answers, so here's my attempt at a full answer to the Harry the barber question:

Well, 1. doesn't give rise to Russell's paradox because Harry doesn't have to shave some of those who don't shave themselves. There can be some unshaven ones around. As long as Harry himself is unshaven the statement isn't violated. Others can remain unshaven too.

But 2. allows Harry to shave some of those who shave themselves. Harry can, indeed - must, shave himself. And all others are also shaven, possibly by both themselves and Harry.

So the inconsistency is between the two, in that in 1. Harry (possibly among others) is unshaven and in 2. Harry (like all the others) is shaven.

Well lets be honest: it isn't really my argument: it's a good job he didnt copyright it [best not say it too loud: a TNC might be listening ]

I know a bit about Wittgensteins theories, because my teacher did his dissertation [i think] on him...

...Its comparable to Berkeley's Idealism, where the emphasis is on the individual existence, doubting the material world and thus placing other's existence in doubt.

I've had a thought...is it cogito ergo sum, or ergo cogito sum: I can't remember!

If you cannot define yourself as an I: what are you? Don;t you define yourseld as an 'I'? What is the definition of 'I'?

tomatoes are red

you are red

therefore you are a tomato

That one always made me chuckle [well developed sense of umour ]

It's 'cogito ergo sum' or 'je pense, donc je suis' when D wrote it in French. He argues that the essence of 'I' is to be a thinking thing.

Well therefore, it takes me to the definition of what thought is rather than what I is...

Thought is what you're doing when you try to come up with a definition of it