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Comment by yellowstuff | Hacker News Reader

Surely the burden of proof is on someone claiming something is impossible? I skimmed the article but I didn't see any support for his argument beyond pointing to the limitations of existing technology, and asserting that these limits were insurmountable.

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If I said I can fly by flapping my arms quickly I would assume the burden of proof would be on me to prove it as opposed to others proving that it's impossible

The argument here is more like: people can’t fly by flapping their arms, therefore human flight is impossible.

The more analogous claim would be "it's impossible to flap two arm-like appendages quickly and achieve flight," and the burden of proof would indeed be on you for making that claim. (Of course, in that case it would be easy to disprove by pointing to birds or even with computer simulations and toys if birds did not exist).

>Surely the burden of proof is on someone claiming something is impossible?

You can't prove a negative in this sense. In general, we know things are possible... but we never know if things are impossible.

And, don't call me surely.

If you can't explain what the difference is between computation and thought how can you hope to argue that one can't be used to achieve the other.

I'm not arguing that it can't. I was merely pointing out the proper 'burden of proof.' The article was criticized for failing to demonstrate that something can't be done... that's not fair. The burden would be on the proponent of the proposition that a machine can attain general AI. That's all.

Perhaps there could be general AI... I'm not saying it can't be done. I would point out, though, that IF it is to be done, it certainly won't be by copying a brain. Nobody even knows the hell the brain works...

Maybe you are stuck on the notion of a computer as a silicon chip. Biological entities are just a special case of machine ergo it is already proved that a machine can attain general AI.

Says who? You are subjectively observing yourself and reality from the inside. How can you be so sure?

There is no proof, or we would not be having this discussion over and over again.

That's certainly not the case. We can and absolutely have proven things to be impossible.

We can and absolutely have proven things to be impossible.

What would you consider to be an example of that? And how does that square with the Problem of Induction which is the hole in our entire system of empirical knowledge generation?

Lots of things in math.

Yes to apply that to the real world, we have to use some assumptions like, the universe isnt a giant trick, the sun will rise tomorrow, we dont live in the matrix, etc. However given the context of this discussion those are fairly reasonable assumptions.

You can’t make a Turing machine which can solve the halting problem or an algorithm which can determine whether any given mathematical statement is true.

You can prove that 2+2!=5. You could even say that, given the rules governing math, it is ‘impossible’ that 2+2=5. The domain, however, is synthetic and composed of a system of axioms and rules.

If I change the underlying axioms and rules, I could certainly prove that 2+2=5, just as I can prove that The sum of a triangles interior angles exceed 180 degrees, or that two identical number squared can equal -1. (Redefining what a straight line means for the former, and inventing an imaginary number system for the latter.)

Proving what can and cannot follow given a set of rules, however, is not what philosophers mean when they speak or impossibility in the real world.

You can give argument though. It is concievable it is possible to prove things like: a turing machine (which is an abstract mathematical model, which we absolutely can prove negatives. See for example rice's theorem) can never achieve "human intellegence" (if you come up with a concrete definition of human intelligence). From there you can make the statement: Any physically realized device that is faithfully modelled in terms of computational power by a turing machine, cannot have "human intelligence".

Sure you can't prove that silicon devices behave like turing machines, or even that they really exist, but for the sake of this discussion, what does that matter?

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