
David Deutsch on why it is so hard to create general AI (2012) - lisper
https://aeon.co/essays/how-close-are-we-to-creating-artificial-intelligence#1
======
lisper
This was previously submitted
([https://news.ycombinator.com/item?id=10919666](https://news.ycombinator.com/item?id=10919666))
but with a very non-descriptive headline: "Creative Blocks", which is just the
name of the column the essay was published in. So I've deliberately subverted
the dup detecter in order to re-submit this piece with a more descriptive
headline.

It's really worth reading.

------
dmfdmf
This is really an excellent essay if you have any interest in AI and the view
that it is a philosophic problem (more specifically, epistemology) and not a
technology or engineering problem. My only comment is that Deutsch assumes
that Popper's theories are correct but they are derivatives of Kant's false
theory of consciousness and false theory of concepts and thus a deadend.

~~~
lisper
I dunno, I find Deutsch's rendition of Popper to be pretty compelling. What
don't you like about it? I haven't read Kant. What do you think he got wrong
that Popper followed?

~~~
dmfdmf
Popper just codified the current state of logic in his "paradigm" of how
science works and his principle of falsifiability. We can prove something
unequivocally false because of Aristotle's principle of non-contradiction but
we can't prove anything unequivocally true (i.e. certain). To do the latter we
need the principles of valid induction. Popper's model of how science works by
proving that old theories are "false" equivocates on the meaning of proof. In
his view Einstein "proved" Newton was wrong but this is not the case. Newton's
theory is true and still true in the context in which it was defined. Einstein
proved a different theory that applied to a wider context of knowledge so he
built on the work of Newton. Einstein himself admitted that his theory was
implicit in Newton's theory. Scientific progress is the accumulation of that
"wider context of knowledge" known (or assumed) to be true, not by proving
things false (though this is part of the process).

Deutsch is throwing the baby out with the bath water by dismissing the problem
of induction as non-sense and a waste of time. The principles of induction
would tell us when a there is enough evidence and in what form to validly say
a statement or theory X is true. Deutsch is right that Hume's question about
how do we know the sun will rise tomorrow is rank skepticism if asked in
today's context (we'd have to ignore everything we know about planets, orbits,
gravity, etc). But somewhere between primitive man's observation that the sun
will rise tomorrow (which is unproved and uncertain knowledge) and modern
man's understanding of astronomy/physics we had enough evidence and crossed an
identifiable line to certainty. Induction defines that line and after crossing
the line the onus would be on the skeptics to explain WHY they think the sun
won't rise tomorrow and their explanation would have to be consistent with
everything we now know, not just some arbitrary dropping of the context.

Everyone is a Kantian today and so I don't think I was going out on a limb to
assume that Popper's theory is an application of Kant's theory. The essence of
Kant's view is that true knowledge is unattainable because we are dependent on
our senses and the world we perceive is "mere" appearances and not reality
itself. This is a denial of consciousness as such and also denies that the
base of knowledge is sensory data. One trap that modern physics has fallen
into is the same Platonic view that the essence of reality is mathematical.
This leads to a whole raft of errors and the solution is a clear understanding
of epistemology and how concepts work.

In any case, Deutsch is groping in the right direction that AI is an
epistemology problem not a technology problem which why I liked his article.

~~~
lisper
> Induction defines that line

Really? How?

> the onus would be on the skeptics to explain WHY they think the sun won't
> rise tomorrow

You've just contradicted yourself, and sided with Deutsch (and hence with
Popper) here by admitting that if a skeptic can explain _why_ the sun won't
rise tomorrow that the skeptic might be right. That's Deutch's (and Poppers)
whole point: it's not about induction, it's about _explanations_.

BTW, it's a question of when, not if, there will come a day when the sun will
no longer rise. The best estimate at the moment is about 5 billion years from
now.

A better example of the failure of induction is this: Barack Obama has been
the president of the United States for about 2500 days now. And he will almost
certainly be the president tomorrow, and the next day, and the day after that.
But I can nonetheless predict with 100% certainty that, one way or another, he
will not be the president one year from today.

~~~
dmfdmf
> Induction defines that line Really? How?

You are asking me to solve the problem of induction. I appreciate your vote of
confidence. ;-)

~~~
lisper
Perhaps I misunderstood you. When you said "Induction defines that line" I
thought that meant you believed that the problem of induction had been solved.
Not necessarily by you, but if you were claiming it had been solved I was just
asking what you thought the solution was.

But I'm still confused then, if you concede that the problem of induction
hasn't been solved, then why do you find the Popper/Deutsch solution to it
(or, if you prefer, end-run around it) so unappealing? Do you _prefer_ a world
where this problem remains unsolved?

~~~
dmfdmf
P1: That was my fault, I didn't state that clearly. I should have said "The
valid principles of induction define that line..." We have the principles of
deduction that tell us when something is false but we are missing the
principles of induction that tell use when something is true (in a given
context). This is a general need so it spans all theories in all fields; how
do we know and are certain the sun will rise, evolution is true, there ARE
atoms, etc. There must be a criteria by which to say, in the current context
of knowledge we know enough to say something is _true_ and certain.

P2: You anticipated my answer, Kant/Popper is an end-run evading the issue,
i.e., we can only prove thing false never true and certain. The truth is
unattainable. I think it is a valid question and needs to be solved. But to
solve it we need a full, valid epistemology explaining how reason works _in
toto_ to achieve _certain_ knowledge.

I think this is the same problem as in physics and all the contradictions and
paradoxes in QM and GR. Physics is hung up on all sorts of confusing issues
that seem to revolve around the nature of the observer and time. This makes
sense to me because deduction is based on a metaphysical fact that
contradictions do not exist which we (try) to abide. But this is half the
story, what is missing is an epistemological principle that tells us what our
brains do to create true knowledge. Whoever solves this problem will
revolutionize physics and allow us to create AI (in my judgement).

~~~
lisper
> what is missing is an epistemological principle that tells us what our
> brains do to create true knowledge

Yes, I think even Deutsch would mostly agree with that, though I think his
position would be: we know what the _principle_ is (universal computation) but
we don't yet know the particular _mechanism_ by which our brains produce new
theories, and that when we do figure that out it will be a major breakthrough.

Anyway, thanks for clarifying.

