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AI’s Language Problem

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Re: AI’s Language Problem

#231

Earlier quoted context omitted.

But a blind person can't describe green. A deaf person can't describe the sound of a motorboat. A person without taste can't describe mint flavor. That is the point I was making. I don't propose that a human could lose all of their senses and still be able to communicate. But I do believe computers could do so, if they are designed to do that. Humans are not designed to work lacking those senses.

So a blind person would never be able to understand the different categories of color (other than that they are placeholders for distinct categories of something). Now we are just speculating. We believe a computer might be able to understand things for which it doesn't have the sense - but that is speculation and totally untested, and certainly can no longer be justified by using human minds as an example.

A blind person could pretend to be sighted though. There have been blind authors who wrote about sighted characters, for instance. They need not experience the thing themselves. Just learn from experience how sighted people behave and describe things, and mimic that.

Re: AI’s Language Problem

#232

Earlier quoted context omitted.

Infact someone has run word2vec on the Voynich manuscript: http://blog.christianperone.com/2016/01/voynich-manuscript-w... (web archive while it's down: http://web.archive.org/web/20160205003817/http://blog.christ... ) Such methods could someday completely decode the thing, but for now they just show the relationships between words and different clusters of words, not their meaning. Of course we have no idea how the…

I'm familiar with this particular attack, as it was discussed here previously. It's a worthwhile attempt but the identification as star names, if real, hasn't been confirmed. But your reservations are justified. More generally, has any attempt been made to identify the meanings of words in any sufficiently large corpus of text in a known foreign language (for example, Finnish), without being provided with a translati…

There was a paper where they trained word vectors for English and Chinese at the same time. But they forced a few Chinese words to have the same vectors as their translated English words. This gave accurate translations for many Chinese words that didn't have translations.

Doing this without any translated words at all, would be more difficult. But I believe possible. It's actually a project I want to try in the near future.

Re: AI’s Language Problem

#233

Earlier quoted context omitted.

I think you mean redundancy. And yes videos are highly redundant. But I don't see how that's any kind of advantage. Text has all the relevant information contained within it, with a ton of irrelevant information discarded. But there are still plenty of learnable patterns. Even trivial algorithms like word2vec can glean a huge amount of semantic information (much easier than is possible with video, currently.) I don't…

>I think you mean redundancy. No, I meant a pair of specific information-theoretical quantities I've been studying. >And yes videos are highly redundant. But I don't see how that's any kind of advantage. Representations are easier to learn for highly-correlated data. Paper forthcoming, but conceptually so obvious that quantifying it is (apparently) non-novel. >I don't know if humans have generative models in their he…

>Representations are easier to learn for highly-correlated data. Paper forthcoming, but conceptually so obvious that quantifying it is (apparently) non-novel.

I know what you are saying, but I don't think it's true.

Imagine a hypothetical language that is so compressed, so non-redundant, so little correlated, that it's indistinguishable from random noise. Learning this language may seem an impossible task. But in fact it's very easy to produce text in this language. Just produce random noise! As stated, that's indistinguishable from real text in this language.

Real language, of course, has tons of statistical patterns, and is definitely not random. But I don't see how it is harder to learn than, say more redundant audio recording of the same words, or a video recording of the person speaking them. That extra information is irrelevant and will just be discarded by any smart algorithm anyway.

>The best available neuroscience and computational cognitive science says we do.

Most people do. As I said some people don't, and they function fine. See this: http://www.bbc.com/news/health-34039054

>Our external behavior is determined by the internal states, insofar as those internal states are functions which map sensory (including proprioceptive and interoceptive) statistics to distributions over actions. If you want your robots to function in society, at least well enough to take it over and kill everyone, they need a good sense of context and good representations for structured information, behavior, and goals.

Robots are never going to have exactly the same internal states and experience as humans. They could be very, very different, in structure, to the human brain. Being exactly like humans isn't the goal. Mimicking humans is an interesting diversion, but it's not necessary, or the goal in and of itself.

And you may be right that a robot without vision would be disadvantaged. I think that's mostly anthropomorphism, imagining how disadvantaged blind humans are (and in fact even blind humans can function better than most people expect.) But even if it's true, my point is that sight is not strictly necessary for intelligence.

In fact I think vision may even be a disadvantage. So much of the brain is devoted to visual processing. While text, and even language itself, are hacks that evolution created relatively recently. A brain built purely for language could be much more efficient at it than we can probably imagine. Ditching vision could save a huge amount of processing power and space.

Re: AI’s Language Problem

#234

Earlier quoted context omitted.

> All of the information of our world is contained in text Even if this were a true statement, it's still the case that it might not be enough. There is a class of functions that are simply not learnable without some prerequisite knowledge. This is directly analogous to a one-time pad in crypto. It is entirely possible that the function 'language' is in this class of unlearnable functions. While it may be the case th…

>There is a class of functions that are simply not learnable without some prerequisite knowledge. This is directly analogous to a one-time pad in crypto. It is entirely possible that the function 'language' is in this class of unlearnable functions. I don't understand how this could possibly be the case. We can already make great progress on language understanding with simple methods like word2vec, or perhaps even ma…

Connotation. Connotation is a huge part of human language, and is completely orthogonal to the denotation, which is what a vector is going to find. For instance, an AI should accurately be able to distinguish the fact that calling someone "cheap" is different from calling them "frugal", even though both objectively mean that the person doesn't spend much money.

There's also the related phenomenon of "subtext" -- the idea that some language has a different meaning than what's said. For instance, when I ask about whether a signature line on a form is required, and the other person says, "Yes, it's required. However you think best to get the signature." There's a subtext there of, "This signature won't actually be checked, so don't worry about it."

Re: AI’s Language Problem

#235

Earlier quoted context omitted.

> All of the information of our world is contained in text. This statement is false. There is a well known thought experiment called Mary’s Room the gist of which is that knowing all conceivable scientific knowledge about how humans perceive color is still not a substitute for being a human and perceiving the color red: https://philosophynow.org/issues/99/What_Did_Mary_Know The experience of seeing red is an example…

The Mary's Room thought experiment is garbage, if you ask me. You can't just assume your hypothesis and then call the result truth. If you assert that a person can understand everything there is to know about the color red and then still not understand what it is like to see red, you have either contradicted yourself or assumed dualism.

They assert that Mary understands the physical phenomenon of red. That is, she understands photons and eye structure, and therefore knows that light of a particular wavelength will trigger these sensors in the eye and thereafter be interpreted as "red" by a brain. All the physical components necessary to produce and sense the color "red". But when Mary sees the apple for the first time, did she learn something more about "red"?

Also, it's a thought experiment. Some people will claim the answer to that question is no, she learned nothing. Others will claim that she did. It's that thing she learned beyond the physical that theoretically cannot be conveyed by science, or even possibly by language.

Re: AI’s Language Problem

#236

Earlier quoted context omitted.

Learning the statistics of language is not going to tell the ML model anything about the underlying stuff to which the language actually refers . It will need actual "sense-data" to do that. For instance, to get a model that generates image captions, you need to train it with actual images. If the much-vaunted "general intelligence" consists in both vague and precise causal reasoning and optimal control with respect…

There is nothing magical about "sense data". A video is just a bunch of 1's and 0's, just like text data. A model of video data is not superior in any way to one of text data, they are just different. The internet is so large and so comprehensive (especially if you include digitized books and papers, e.g. libgen or google books) that I doubt any important information that can be learned through video data, can't be o…

A video is encoded to a series of ones and zeros by a codex. That codex determines the interpretation of that data. The codex basically becomes a sensor -- it serves the same purpose as the eyes, which is taking raw data (photon excitements or binary string) and turning it into meaningful data (an image). And without that codex, the information is basically meaningless.

Re: AI’s Language Problem

#237
post #176

Earlier quoted context omitted.

So a related question becomes, can you learn to understand and thus predict physics (the way a child does - I'm not talking about quantum mechanics) from literature only, without interacting in space?

> from literature only How about when you include multimedia recordings? Or give the machine a camera and wheels?

Giving the machine a camera and wheels is basically embedding it in the real world. It goes against the spirit of my question, and since I was asking it skeptically it's actually the thing I intuitively (without any relevant expertise!) expect to be required.

Re: AI’s Language Problem

#238

Earlier quoted context omitted.

>I think you mean redundancy. No, I meant a pair of specific information-theoretical quantities I've been studying. >And yes videos are highly redundant. But I don't see how that's any kind of advantage. Representations are easier to learn for highly-correlated data. Paper forthcoming, but conceptually so obvious that quantifying it is (apparently) non-novel. >I don't know if humans have generative models in their he…

>Representations are easier to learn for highly-correlated data. Paper forthcoming, but conceptually so obvious that quantifying it is (apparently) non-novel. I know what you are saying, but I don't think it's true. Imagine a hypothetical language that is so compressed, so non-redundant, so little correlated, that it's indistinguishable from random noise. Learning this language may seem an impossible task. But in fac…

>I know what you are saying, but I don't think it's true.

Reading your post, you actually seem quite confused.

>Imagine a hypothetical language that is so compressed, so non-redundant, so little correlated, that it's indistinguishable from random noise. Learning this language may seem an impossible task.

Well yes, learning a class of strings in which each digit of every finite prefix is statistically independent from each other digit, is very hard, bordering on impossible (or at least, impossible to do better than uniform-random guessing).

>But in fact it's very easy to produce text in this language. Just produce random noise!

But that isn't the learning problem being posed! You are not being asked to learn `P(string | language)` (which is, in fact, the uniform distribution over arbitrary-length strings), but `P(language | string1, string2, ..., stringn)`, which by the way you've posed the problem factorizes into `P(language| character1) x P(language|character2) x ... x P(language|characterm)`. If the actual strings are sampled from a uniform distribution over arbitrary-length strings, then we have two possibilities:

1) The prior is over a class of languages some of which are not optimally compressed, and which thus do not render each character (or even each string) conditionally independent. In this case, the posterior will favor languages that do render each character conditionally independent, but we won't be able to tell apart one such hypothesis from another. We've learned very little.

2) The prior is over a class of languages all of which yield strings full of conditionally-independent noise: no hypothesis can compress the data. In this case, the evidence-probability and the likelihood cancel, and our posterior over languages equals our prior (we've learned nothing).

>Real language, of course, has tons of statistical patterns, and is definitely not random. But I don't see how it is harder to learn than, say more redundant audio recording of the same words, or a video recording of the person speaking them. That extra information is irrelevant and will just be discarded by any smart algorithm anyway.

Noooo. Compression does not work that way. Compression works by finding informative patterns in data, not by throwing them away. If your goal is to learn the structure in the data, you want the structure to be more redundant rather than less.

I'm telling you, once the paper is submitted, I can send you a copy and just show you the equations and inequalities demonstrating this fact.

>Most people do. As I said some people don't, and they function fine. See this: http://www.bbc.com/news/health-34039054

Differences in sensorimotor cortex function that leave the brain unable to perform top-down offline simulation with a high subjective-sensory precision don't invalidate the broad theory that cortical microcircuits are generative models (in particular, hierarchical ones, possibly just large hierarchies in which the individual nodes are very simple distributions).

http://www.fil.ion.ucl.ac.uk/~karl/The%20free-energy%20princ...

>Robots are never going to have exactly the same internal states and experience as humans. They could be very, very different, in structure, to the human brain.

Duh. However, if we want them to work, they probably have to run on free-energy minimization somehow. There is more necessity at work here than connectionism believes in, but that's a fault in connectionism.

>Being exactly like humans isn't the goal. Mimicking humans is an interesting diversion, but it's not necessary, or the goal in and of itself.

I didn't say that a working robot's representations had to exactly match those of humans. In fact, doing so would be downright inefficient, since robots would have completely different embodiments to work with, and thus be posed different inference problems in both perception and action. The fact that they would be, necessarily, inference problems is the shared fact.

>And you may be right that a robot without vision would be disadvantaged. I think that's mostly anthropomorphism, imagining how disadvantaged blind humans are (and in fact even blind humans can function better than most people expect.) But even if it's true, my point is that sight is not strictly necessary for intelligence.

Sight isn't. Some kind of high-dimensional sense-data is.

>In fact I think vision may even be a disadvantage. So much of the brain is devoted to visual processing. While text, and even language itself, are hacks that evolution created relatively recently. A brain built purely for language could be much more efficient at it than we can probably imagine. Ditching vision could save a huge amount of processing power and space.

That's putting the cart before the horse. Language is, again, an efficient but redundant (ie: robust against noise) code for the models (ie: knowledge, intuitive theories, as you like) the brain already wields. You can take the linguistic usage statistics of a word and construct a causal-role concept for them in the absence of a verbal definition or sensory grounding for the word, which is arguably what children do when we read a word before anyone has taught it to us, but doing so will only work well when the concepts' definitions are themselves mostly ungrounded and abstract.

So purely linguistic processing would work fairly well for, say, some of mathematics, but not so much for more empirical fields like social interaction, ballistic-missile targeting, and the proper phrasing of demands made to world leaders in exchange for not blowing up the human race.

Re: AI’s Language Problem

#239

Earlier quoted context omitted.

>Representations are easier to learn for highly-correlated data. Paper forthcoming, but conceptually so obvious that quantifying it is (apparently) non-novel. I know what you are saying, but I don't think it's true. Imagine a hypothetical language that is so compressed, so non-redundant, so little correlated, that it's indistinguishable from random noise. Learning this language may seem an impossible task. But in fac…

>I know what you are saying, but I don't think it's true. Reading your post, you actually seem quite confused. >Imagine a hypothetical language that is so compressed, so non-redundant, so little correlated, that it's indistinguishable from random noise. Learning this language may seem an impossible task. Well yes, learning a class of strings in which each digit of every finite prefix is statistically independent from…

>But that isn't the learning problem being posed! You are not being asked to learn `P(string | language)` (which is, in fact, the uniform distribution over arbitrary-length strings), but `P(language | string1, string2, ..., stringn)`...

Hold on. Let's say the goal is passing a Turing test. I think that's sufficient to demonstrate general intelligence and do useful work. In that case, all that is required is mimicry. All you need to know is P(string), and you can produce text indistinguishable from a human.

>Noooo. Compression does not work that way. Compression works by finding informative patterns in data, not by throwing them away. If your goal is to learn the structure in the data, you want the structure to be more redundant rather than less.

Ok lets say I convert English words to smaller huffman codes. This should be even easier for a neural network to learn, because it can spend less effort trying to figure out spelling. Of course some encodings might make it harder for a neural net to learn, since NNs make some assumptions about how the input should be structured, but in theory it doesn't matter.

>Some kind of high-dimensional sense-data is [necessary]... purely linguistic processing would work fairly well for, say, some of mathematics, but not so much for more empirical fields

These are some really strong assertions that I just don't buy, and I don't think you've backed up at all.

Humans have produced more than enough language for a sufficiently smart algorithm to construct a world model from it. Any fact you can imagine is contained somewhere in the vast corpus of all English text. English contains a huge amount of patterns that give massive hints to the meaning. E.g. that kings are male, or that males shave their face and females typically don't, or that cars are associated with roads, which is a type of transportation, etc.

Even very crude models can learn these things. Even very crude models can produce nearly sensible dialogue from movie scripts. Models with millions of times fewer nodes than the human brain. It's amazing this is possible at all. Of course a full AGI should be able to do a thousand times better and completely understand English.

Trying to model video data first is wasted processing power. It's setting the field back. Really smart researchers spend so much time eeking out 0.01% better benchmark on MNIST/imagenet/whatever, with entirely domain specific, non general methods. So much effort is put into machine vision, when Language is so much more interesting and useful, and closer to general intelligence. Convnets, et al., are a dead end, at least for AGI.

Re: AI’s Language Problem

#240

Earlier quoted context omitted.

The very method of using a word embedding space assumes the manifold is smooth, so the fact that vectors extracted from a method that assumes a smooth manifold, are in fact on a smooth manifold, is just circular and not evidence of anything.

The evidence is that this works in the first place.

That is very, very weak evidence.
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