Category: Cognitive Science

Free Will and Algorithmic Information Theory

Mark Davis1 Comment

I was recently looking for examples of applications of algorithmic information theory, also commonly called algorithmic information complexity (AIC). After all, for a theory to be sound is one thing, but when it is sound and valuable it moves to another level. So, first, let’s review the broad outline of AIC. AIC begins with the problem of randomness, specifically random strings of 0s and 1s. We can readily see that given any sort of encoding in any base, strings of characters can be reduced to a binary sequence. Likewise integers.

Now, AIC states that there are often many Turing machines that could generate a given string and, since we can represent those machines also as a bit sequence, there is at least one machine that has the shortest bit sequence while still producing the target string. In fact, if the shortest machine is as long or a bit longer (given some machine encoding requirements), then the string is said to be AIC random. In other words, no compression of the string is possible.

Moreover, we can generalize this generator machine idea to claim that given some set of strings that represent the data of a given phenomena (let’s say natural occurrences), the smallest generator machine that covers all the data is a “theoretical model” of the data and the underlying phenomena. An interesting outcome of this theory is that it can be shown that there is, in fact, no algorithm (or meta-machine) that can find the smallest generator for any given sequence. This is related to Turing Incompleteness.

In terms of applications, Gregory Chaitin, who is one of the originators of the core ideas of AIC, has proposed that the theory sheds light on questions of meta-mathematics and specifically that it demonstrates that mathematics is a quasi-empirical pursuit capable of producing new methods rather than being idealistically derived from analytic first-principles.… Read the rest

Hypersensitive Conspiracy Disorder

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I was once cornered in a bar in Suva, Fiji by an Indian man who wanted to unburden himself and complain a bit. He was convinced that the United States had orchestrated the coups of 1987 in which the ethnically Fijian-dominated military took control of the country. The theory went like this: ethnic Indians had too much power for the Americans to bear as we were losing Subic Bay as a deep water naval base in the South Pacific. Suva was the best, nearest alternative but the Indians, with their cultural and political ties to New Delhi, were too socialist for the Americans. Hence the easy solution was to replace the elected government with a more pro-American authoritarian regime. Yet another Cold War dirty tricks effort, like Mossaddegh or Allende, far enough away that the American people just shrugged our collective shoulders. My drinking friend’s core evidence was an alleged sighting of Oliver North by someone, sometime, chatting with government officials. Ollie was the 4D chess grandmaster of the late 80s.

It didn’t work out that way, of course, and the coups continued into the 2000s. More amazing still was that the Berlin Wall came down within weeks of that bar meetup and the entire engagement model for world orders slid into a brief decade of deconstruction and confusion. Even the economic dominance of Japan ebbed and dissipated around the same time.

But our collective penchant for conspiracy theories never waned. And with the growth of the internet and then social media, the speed and ease of disseminating fringe and conspiratorial ideas has only increased. In the past week there were a number of news articles about the role of conspiracy theories, from a so-called “QAnon” advocate meeting with Trump to manipulation of the government by Israel’s Black Cube group.… Read the rest

Running, Ancient Roman Science, Arizona Dive Bars, and Lightning Machine Learning

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I just returned from running in Chiricahua National Monument, Sedona, Painted Desert, and Petrified Forest National Park, taking advantage of the late spring before the heat becomes too intense. Even so, though I got to Massai Point in Chiricahua through 90+ degree canyons and had around a liter of water left, I still had to slow down and walk out after running short of liquid nourishment two-thirds down. There is an eerie, uncertain nausea that hits when hydration runs low under high stress. Cliffs and steep ravines take on a wolfish quality. The mind works to control feet against stumbling and the lips get serrated edges of parched skin that bite off without relieving the dryness.

I would remember that days later as I prepped to overnight with a wilderness permit in Petrified Forest only to discover that my Osprey Exos pack frame had somehow been bent, likely due to excessive manhandling by airport checked baggage weeks earlier. I considered my options and drove eighty miles to Flagstaff to replace the pack, then back again.

I arrived in time to join Dr. Richard Carrier in an unexpected dive bar in Holbrook, Arizona as the sunlight turned to amber and a platoon of Navajo pool sharks descended on the place for billiards and beers. I had read that Dr. Carrier would be stopping there and it was convenient to my next excursion, so I picked up signed copies of his new book, The Scientist in the Early Roman Empire, as well as his classic, On the Historicity of Jesus, that remains part of the controversial samizdat of so-called “Jesus mythicism.”

If there is a distinguishing characteristic of OHJ it is the application of Bayesian Theory to the problems of historical method.… Read the rest

Black and Gray Boxes with Autonomous Meta-Cognition

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Vijay Pande of VC Andreessen Horowitz (who passed on my startups twice but, hey, it’s just business!) has a relevant article in New York Times concerning fears of the “black box” of deep learning and related methods: is the lack of explainability and limited capacity for interrogation of the underlying decision making a deal-breaker for applications to critical areas like medical diagnosis or parole decisions? His point is simple, and related to the previous post’s suggestion of the potential limitations of our capacity to truly understand many aspects of human cognition. Even the doctor may only be able to point to a nebulous collection of clinical experiences when it comes to certain observational aspects of their jobs, like in reading images for indicators of cancer. At least the algorithm has been trained on a significantly larger collection of data than the doctor could ever encounter in a professional lifetime.

So the human is almost as much a black box (maybe a gray box?) as the algorithm. One difference that needs to be considered, however, is that the deep learning algorithm might make unexpected errors when confronted with unexpected inputs. The classic example from the early history of artificial neural networks involved a DARPA test of detecting military tanks in photographs. The apocryphal to legendary formulation of the story is that there was a difference in the cloud cover between the tank images and the non-tank images. The end result was that the system performed spectacularly on the training and test data sets but then failed miserably on new data that lacked the cloud cover factor. I recalled this slightly differently recently and substituted film grain for the cloudiness. In any case, it became a discussion point about the limits of data-driven learning that showed how radically incorrect solutions could be created without careful understanding of how the systems work.… Read the rest

Deep Simulation in the Southern Hemisphere

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I’m unusually behind in my postings due to travel. I’ve been prepping for and now deep inside a fresh pass through New Zealand after two years away. The complexity of the place seems to have a certain draw for me that has lured me back, yet again, to backcountry tramping amongst the volcanoes and glaciers, and to leasurely beachfront restaurants painted with eruptions of summer flowers fueled by the regular rains.

I recently wrote a technical proposal that rounded up a number of the most recent advances in deep learning neural networks. In each case, like with Google’s transformer architecture, there is a modest enhancement that is based on a realization of a deficit in the performance of one of two broad types of networks, recurrent and convolutional.

An old question is whether we learn anything about human cognition if we just simulate it using some kind of automatically learning mechanism. That is, if we use a model acquired through some kind of supervised or unsupervised learning, can we say we know anything about the original mind and its processes?

We can at least say that the learning methodology appears to be capable of achieving the technical result we were looking for. But it also might mean something a bit different: that there is not much more interesting going on in the original mind. In this radical corner sits the idea that cognitive processes in people are tactical responses left over from early human evolution. All you can learn from them is that they may be biased and tilted towards that early human condition, but beyond that things just are the way they turned out.

If we take this position, then, we might have to discard certain aspects of the social sciences.… Read the rest

Ambiguously Slobbering Dogs

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I was initially dismissive of this note from Google Research on improving machine translation via Deep Learning Networks by adding in a sentence-level network. My goodness, they’ve rediscovered anaphora and co-reference resolution! Next thing they will try is some kind of network-based slot-filler ontology to carry gender metadata. But their goal was to add a framework to their existing recurrent neural network architecture that would support a weak, sentence-level resolution of translational ambiguities while still allowing the TPU/GPU accelerators they have created to function efficiently. It’s a hack, but one that potentially solves yet another corner of the translation problem and might result in a few percent further improvements in the quality of the translation.

But consider the following sentences:

The dog had the ball. It was covered with slobber.

The dog had the ball. It was thinking about lunch while it played.

In these cases, the anaphora gets resolved by semantics and the resolution seems largely an automatic and subconscious process to us as native speakers. If we had to translate these into a second language, however, we would be able to articulate that there are specific reasons for correctly assigning the “It” to the ball in the first two sentences. Well, it might be possible for the dog to be covered with slobber, but we would guess the sentence writer would intentionally avoid that ambiguity. The second set of sentences could conceivably be ambiguous if, in the broader context, the ball was some intelligent entity controlling the dog. Still, when our guesses are limited to the sentence pairs in isolation we would assign the obvious interpretations. Moreover, we can resolve giant, honking passage-level ambiguities with ease, where the author is showing off in not resolving the co-referents until obscenely late in the text.… Read the rest

Brain Gibberish with a Convincing Heart

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Elon Musk believes that direct brain interfaces will help people better transmit ideas to one another in addition to just allowing thought-to-text generation. But there is a fundamental problem with this idea. Let’s take Hubert Dreyfus’ conception of the way meaning works as being tied to a more holistic view of our social interactions with others. Hilary Putnam would probably agree with this perspective, though now I am speaking for two dead philosphers of mind. We can certainly conclude that my mental states when thinking about the statement “snow is white” are, borrowing from Putnam who borrows from Quine, different from a German person thinking “Schnee ist weiß.” The orthography, grammar, and pronunciation are different to begin with. Then there is what seems to transpire when I think about that statement: mild visualizations of white snow-laden rocks above a small stream for instance, or, just now, Joni Mitchell’s “As snow gathers like bolts of lace/Waltzing on a ballroom girl.” The centrality or some kind of logical ground that merely asserts that such a statement is a propositional truth that is shared in some kind of mind interlingua doesn’t bear much fruit to the complexities of what such a statement entails.

Religious and political terminology is notoriously elastic. Indeed, for the former, it hardly even seems coherent to talk about the concept of supernatural things or events. If they are detectable by any other sense than some kind of unverifiable gnosis, then they are at least natural in that they are manifesting in the observable world. So supernatural imposes a barrier that seems to preclude any kind of discussion using ordinary language. The only thing left is a collection of metaphysical assumptions that, in lacking any sort of reference, must merely conform to the patterns of synonymy, metonymy, and other language games that we ordinarily reserve for discernible events and things.… Read the rest

The Obsessive Dreyfus-Hawking Conundrum

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I’ve been obsessed lately. I was up at 5 A.M. yesterday and drove to Ruidoso to do some hiking (trails T93 to T92, if interested). The San Augustin Pass was desolate as the sun began breaking over, so I inched up into triple digit speeds in the M6. Because that is what the machine is made for. Booming across White Sands Missile Range, I recalled watching base police work with National Park Rangers to chase oryx down the highway while early F117s practiced touch-and-gos at Holloman in the background, and then driving my carpool truck out to the high energy laser site or desert ship to deliver documents.

I settled into Starbucks an hour and a half later and started writing on ¡Reconquista!, cranking out thousands of words before trying to track down the trailhead and starting on my hike. (I would have run the thing but wanted to go to lunch later and didn’t have access to a shower. Neither restaurant nor diners deserve an après-run moi.) And then I was on the trail and I kept stopping and taking plot and dialogue notes, revisiting little vignettes and annotating enhancements that I would later salt in to the main text over lunch. And I kept rummaging through the development of characters, refining and sifting the facts of their lives through different sets of sieves until they took on both a greater valence within the story arc and, often, more comedic value.

I was obsessed and remain so. It is a joyous thing to be in this state, comparable only to working on large-scale software systems when the hours melt away and meals slip as one cranks through problem after problem, building and modulating the subsystems until the units begin to sing together like a chorus.… Read the rest

Tweak, Memory

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Artificial Neural Networks (ANNs) were, from early on in their formulation as Threshold Logic Units (TLUs) or Perceptrons, mostly focused on non-sequential decision-making tasks. With the invention of back-propagation training methods, the application to static presentations of data became somewhat fixed as a methodology. During the 90s Support Vector Machines became the rage and then Random Forests and other ensemble approaches held significant mindshare. ANNs receded into the distance as a quaint, historical approach that was fairly computationally expensive and opaque when compared to the other methods.

But Deep Learning has brought the ANN back through a combination of improvements, both minor and major. The most important enhancements include pre-training of the networks as auto-encoders prior to pursuing error-based training using back-propagation or  Contrastive Divergence with Gibbs Sampling. The critical other enhancement derives from Schmidhuber and others work in the 90s on managing temporal presentations to ANNs so the can effectively process sequences of signals. This latter development is critical for processing speech, written language, grammar, changes in video state, etc. Back-propagation without some form of recurrent network structure or memory management washes out the error signal that is needed for adjusting the weights of the networks. And it should be noted that increased compute fire-power using GPUs and custom chips has accelerated training performance enough that experimental cycles are within the range of doable.

Note that these are what might be called “computer science” issues rather than “brain science” issues. Researchers are drawing rough analogies between some observed properties of real neuronal systems (neurons fire and connect together) but then are pursuing a more abstract question as to how a very simple computational model of such neural networks can learn.… Read the rest

Apprendre à traduire

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Google’s translate has always been a useful tool for awkward gists of short texts. The method used was based on building a phrase-based statistical translation model. To do this, you gather up “parallel” texts that are existing, human, translations. You then “align” them by trying to find the most likely corresponding phrases in each sentence or sets of sentences. Often, between languages, fewer or more sentences will be used to express the same ideas. Once you have that collection of phrasal translation candidates, you can guess the most likely translation of a new sentence by looking up the sequence of likely phrase groups that correspond to that sentence. IBM was the progenitor of this approach in the late 1980’s.

It’s simple and elegant, but it always was criticized for telling us very little about language. Other methods that use techniques like interlingual transfer and parsers showed a more linguist-friendly face. In these methods, the source language is parsed into a parse tree and then that parse tree is converted into a generic representation of the meaning of the sentence. Next a generator uses that representation to create a surface form rendering in the target language. The interlingua must be like the deep meaning of linguistic theories, though the computer science versions of it tended to look a lot like ontological representations with fixed meanings. Flexibility was never the strong suit of these approaches, but their flaws were much deeper than just that.

For one, nobody was able to build a robust parser for any particular language. Next, the ontology was never vast enough to accommodate the rich productivity of real human language. Generators, being the inverse of the parser, remained only toy projects in the computational linguistic community.… Read the rest