- The brain is more fuzzy, but it still stores the link between the smell of roses and the look of roses. Just as a probability, like a Bayes network. And you will fall for Illusions, just like a Bayes network can be wrong ("for a second I thought this was..." and than more information from the senses falsifies/corrects the probabilities).
- The brain is imperfect in reading from memory, but it still does. It just uses really good, lossy compression. It's loosing much detail, but often filling holes probabilistically. Besides neural nets, in computers this would be: defaults, recovery blocks etc. In part the good compression comes from an additional layer of abstraction, but computers can do this too. A very simple example are the the blurry color layers in jpg.
- We are better at recognizing than recalling, because a highly compressed memory is not enough to recreate the original, but has enough indicators to verify. This us very much like a checksum.
What there is, is the bias of the "hardware". Our brains are not good at deterministic iterations, computers struggle with the complexity of forming wisdom and fuzziness and feedback does not come naturally to them either. But in principle, we are both turing complete or something :)
Right, I don't see the point of this article. At first I thought it's the yearly "humans have a soul and are better than AI algorithms" story we get.
Of course a mere year ago the fact that computers can't get good moves in Go was an argument. And all the arguments that came before that, voice recognition, reading, chess, games, even counting itself at one point. Of all those things that computers/"information processing" couldn't achieve we now know : computers have recognized more spoken text, read more books, letters, envelopes and ... than humans ever will. Computers have played more chess games, and certainly have processed more numbers than humans ever did or ever will. Humans probably still have a mild advantage in amount of Go processing, but it's clear that's not going to last much longer either.
This article takes another approach : because the type of processing that happens in our minds differs "so much" from what we do with computers, they must be fundamentally different. The emphasis lies on the human mind being different : humans don't work like computers, not the opposite. That wouldn't work : because computers do work like humans. That's why we build them, and use them. Computers analyse stocks, sell apples and cars and home insurance, they mail letters, they work out what a business should schedule tomorrow, they move their arms to glue soles onto shoes, ...
One might also analyse why computers are working so very differently. Why Von Neumann ? Well, because we don't really know ahead of time what we want computers to do, and even when we do, we want the ability to change it later. We want computers, to a large extent, and maybe even to 100%, to work like humans do, but we can't do that. As illustrated above, we get closer every year. Computers simulate other machines, that's what they do. So what you should compare is not instruction sets versus neurons, but neural network models those instruction sets simulate with biological neurons.
And then the differences melt away. Not fully. Not yet. We don't know how. Not fully. Not yet.
The point of this article is the argument that the metaphor that human brains work just like computers is leading people astray in figuring out how human brains actually do work.
Maybe we don't know how human brains actually do work (in my opinion we do, but for the sake of the discussion..) but we know what they do: brains compute.
He really didn't show where people are struggling due to that supposed handicap. He also didn't show why brains aren't literally performing the task of computing.
I mean shit, if I judge the distance between two points, how can it not be said that I have collected sensory data and computed the result?
"We don't build machines in order to raise them and love them; we build them to get work done.
If the thing is even remotely close to "intelligent", you can no longer issue commands; you must explain yourself and ask for something and then it will misunderstand you. Normal for a person, pretty shitty for a machine. Humans have the sacred right to make mistakes. Machines should be working as designed."
One look at the age pyramid of the world, or fertility statistics, will immediately drive home the point that we will in fact build machines to raise them and love them. I mean even in the places that for some reason currently feel comfortable with their birth statistics, there's no denying that the current generation is the last one to be larger than the one that came before it. In most countries, even that is not the case. In the US, GenX is the last one that was larger than the one before it, and only by the teensiest of margins. In Europe, that would have happened in the 80s.
A "child" that requires far less resources will be a product that will be incredibly popular. Not to mention an economic necessity.
And I would even say : 100 billion "small" AIs (scale vaguely comparable to a human mind) is a far preferable situation to one big AI. Both from a survivability standpoint and from an "oh my God it'll kill us all" standpoint.
> "We don't build machines in order to raise them and love them; we build them to get work done.
I would even say, if it's at all possible we'll do just that in the next 10-15 years. If we don't get advanced enough AI, perhaps 20-25 years.
I sort of get you, personally I feel the same. But then I walk around here and see people with dogs in baby carriages. Why ? Because they could never have a child, they're too old, or cannot or don't want to spend the money they think it'll require.
The problem does not tend to be that it's physically impossible to get a child.
To add on to the image compression theory, I read somewhere (maybe here on HN) that perhaps many image memories are stored as difference from a "nominal" representation. So one might not remember a complete face for example, but rather the features that stood out from a "normal face".
Agreed. This article struck me as exceedingly pedantic.
Given the author's background, I'd put money on the idea that this is the result of years of frustration at having his life's work dismissively reduced by casual observers to something like "yeah, it's basically a computer" and thinking they therefore understand all the intricacies of the human brain. I can see how that might grate on a person in his field and trigger a response like this.
It's not even pedantic, it's just wrong. He's ignoring years of neuroscience.
We know that the brain uses signals, and that these signals are composed of codes. We know that to interpret the world, certain information processing must take place. We are learning more about the exact nature of this processing, more about how neurons and even other fundamentals of the body code information and contribute to processing (e.g. chemical processes), but they definitely process information. We even know some of the codes.
On the other hand, if the author wants to argue about the nature of what is information, what is processing.. he's going to have a steep hill to climb.
Well, afaik we can't easily record individual neurons inside the brain, although there are some studies towards that goal. Most brain studies work on areas of activity. Even MRI is not that precise, to be frank. But for studying human perception, a technique often used is called microneurography, which involves sticking a probe into the nerve fibers along a known neural pathway and recording the electrical stimulations.
From this we can often find things like:
- frequency of impulses increases as stimulus increases
- different numbers of neurons in a similar area fire simultaneously
Things like that. The wikipedia articles linked by wickedagain contain a good summary. I won't link specific sources, since there are thousands, but here's one for instance:
There in fig 6 for example you can see that the frequency of nerve firing increases in the tibial nerve as heat is applied to the paw. (Yes, a lot of information comes from horrible animal studies. It's part of the reason I didn't continue in this domain of work -- although rest assured, this technique is possible with humans, without harm.)
So, do impulses in the perceptual nervous system reflect how brains work, how we think? It's hard to say for sure, but it's clear that information is coded according to certain possibilities related to how neurons work, and this information must be combined and processed somehow to create what we call perceptions. Is it such a stretch to imagine that these perceptions become their own codes, abstract reductions of correlations of perceptual information, that are evaluated, compared, and combined in the much, much more nerve-dense central cortex to produce what we call "thought"?
A human being is not a machine just as "a brain" is not a computer. To say that the sum is greater than the individual parts is truly an understatement. I find it sad that scientists are so naive. The brain exists to tell the body what not to do. No machine will ever be able to replace it no matter how much you think you know about it.
A further frustration might be with computers themselves. I don't see why an introduction/exposition to computing should be something that needs pardon.
Bravo. You can understand that only if you offer an abstract definition of terms like 'computer', 'computation', 'calculation' etc. If you define 'computing' as something these clusters of regular matter we call 'computers' do, then if would exclude animals and other things. But, when you're thinking in abstract terms, then you come to the conclusion that a lot of things in nature are 'computing'.
The same thing could be said about 'intelligence'. Current definitions of intelligence are not abstract definitions(even though the word itself seems like some abstract term, similar to calculation, motion etc.), but rather are labels/descriptions of particular human traits. If a more abstract definition was offered, you would see a lot more things in nature 'becoming' intelligent. So, currently we are in a situation where 'intelligence' is defined in terms of human traits(like being able to speak human language, do human mathematics, drive cars etc), but then at the same time we're looking for intelligent aliens. You can't find 'intelligent' aliens if the term intelligence is defined in such a way to only ever apply to humans. It's really a parlor trick.
This is an expression of human desire to feel special - you don't want to be labeled as a computer or cluster of regular matter - rather you are an 'intelligent' soul(a different substance, not a regular matter) made in the image of the most powerful creature in the universe who happens to love you and care about you.
Current definitions of intelligence are not abstract definitions [..] but rather are labels/descriptions of particular human traits.
Agreed with the rest of what you wrote, but "intelligence" is more or less uniformly defined as the ability to quickly assimilate and apply information. What we try to measure is the speed, accuracy and complexity of that process. We have tried to measure the same process with dogs, parrots, monkeys, and ravens, and we even use comparable scales (e.g. general opinion is that adult dogs can handle the same mental complexity as toddlers).
You are correct that the tests we use incorporate human traits. But that's as much because we are mainly testing humans as because we use humans as our reference.
The definition you've offered is an abstract definition, but it's not the one used in experiments and in everyday life.
What these experiments with animals are designed for is to check which animals can do things in a similar way to humans.
Why are ravens intelligent? Is it because they can quickly process information? No, that is not what experiments are checking. They are labelled as intelligent because they can use tools to unlock their food.
Why are dolphins intelligent? Is it because they process complex information quickly? No, it's because they have large brains and exhibit empathy towards humans plus they seem to be able to communicate with each other.
People don't say "Well, that system can process complex information quickly, therefore it's intelligent". Instead, what you'll hear is "WOW, animal X can use tools, can communicate, organize in groups! They are more intelligent that we thought". Using tools or communicating is just one way of processing information. There are many other ways. For example, an animal might not be able to use tools in a cage to unlock their food, but they could be a terrific fighter in the jungle. Fighting in a jungle is a process that demands quick information processing, but those animals are somehow below in intelligence than revens or dogs. That is because people aren't using the definition you've provided.
> You are correct that the tests we use incorporate human traits. But that's as much because we are mainly testing humans as because we use humans as our reference.
There is no need to incorporate human traits, because you've already defined the term in a good way. Why do you need humans for reference? You have the definition, you can provide measurement for speed (X per second) and you're good to go. You don't use humans to measure acceleration of objects, so why would you use humans to measure intelligence?
- The brain's network is not very well understood. For example, half your body's neurons are in your cerebellum. There people that don't have a cerebellum, and they only seem to walk later, and have balance issues [0]. That is half of all your neurons, and until you do a scan, people can't tell you are missing them. Alternatively, we have Henry Molaison (known in literature as HM), who could not remember a thing from after his surgery to save his life. All the surgeons took was his hippocampus (and some other stuff) back in 1953, which we then found out was SUPER important for memory [1]. He lived to be 82 and died in 2008, incidentally. Suffice to say, the neurons, their local network, and the long range network (aka, your whole body) are all very important in terms of how it all works. You can take out a ton, and not loose really anything, or you can take out some special ones and never remember a thing again. The brain is not 'fuzzy' and really 'fuzzy' all at the same time. It's like lumping all of China's politics into just their Chairman's ideas; you loose any sense of what is going on.
-The brain's recall system is also not well known. As with HM's life, you take out this special part, and it all goes to shit. However, when HM sang or played music, he could do an entire song or piece, even if it was Indagardadavida's length. Also, he remembered shocks to his hand when a surgeon put a joke buzzer in one day; he was hesitant to shake the next day. Our memory is not in any way good or lossy. Look at PTSD victims, they remember it ALL. Typically, it comes down to the motivations of the person. If you have to remember for the future, like an important fact for a test, or the sound a wolf makes right before it leaps onto you, then you will remember it very well. If you don't need to remember, then you typically do not. Again though, the brain is not well understood and we all have experienced exceptions to this.
-Some people are better at recognizing, some are better at recalling, and we don't know why. People that are face blind [2] are really bad at remembering faces; Brad Pitt says that he is face blind. Some people are really good with faces and really bad with names, some are the opposite. Some are synesthetes [3] and will recall equations or speeches by the taste that they experience when doing it. Some people are savants and can recall an entire phonebook and then draw it, nearly as a cc, from memory [4]. Memory is a fascinating subject and whenever you think you know what is going on, something new opos up and kills the theory.
-Our brains can be very good at deterministic calculations. Any major league ballplayer is very good in the outfield (the D-backs excepted this year) and can very accurately catch a ball hit from 100s of feet away. They may not be good with math, but some of them are much better than any computer [5].
The brain is not well understood at this time. Calling it a computer is obvious nonsense, but it's a good working theory to approach from, especially considering we have no other real ideas.
Provocatively naive - does anyone nowadays really think the brain Works like a computer? A much more interesting focus is on non-representationalistic understandings of the world seen in the discussion.
Ok. For one, we really still don't know a lot about the brain. Secondly, well...as far as I can tell, the brain is like an computer that adds more and more traces as it goes. The logic is the circuit, no real analogue to software. The hardware is the algorithm, and we can add new hardware. There is storage, but it's fuzzy...with a MTBF that's not well understood. The actions that we take are based on potentials, just like in a circuit with sense amps that aren't perfectly tuned, nor is the switch amp binary....there's a lot of muxing going on (again, that we don't understand). But to say that the brain isn't like a computer is extremely naive. Cells make up the brain, each cell's logic can be worked out using well...logic. Putting those cells together into a complex system produces behavior that is obviously complex, and hard to understand. Ever tried to understand the behavior of a multi-threaded, multi-node, multi-socket compute system down to the microsecond? It's complex right? Yeah, we barely can grasp that, give it a few decades and we'll probably figure out a bit more about how the brain works...and how to quantify it.
BRAINS ARE COMPUTERS is a useful conceptual metaphor for many purposes. But metaphors are imperfect. It's not literally true that LIFE IS A JOURNEY or SOCIAL ORGANIZATIONS ARE PLANTS.
This article falls somewhere between a strawman argument and a deliberate misrepresentation of scientific understanding.
> "But here is what we are not born with: information, data, rules, software, knowledge, lexicons, representations, algorithms, programs, models, memories, images, processors, subroutines, encoders, decoders, symbols, or buffers"
We are born with most (if not) all of these things, and we develop more of them as we grow and learn. Sure, the nomenclature here was chosen for ridicule, but functionally those elements are present.
The brain is not a magical pudding that works in a completely occult and mysterious manner. While we do have a ways to go in deciphering the minutiae of its architecture and operation, the article engages in assertions that run completely counter to neurobiological facts we have already learned:
> "We don’t store words or the rules that tell us how to manipulate them. We don’t create representations of visual stimuli, store them in a short-term memory buffer, and then transfer the representation into a long-term memory device. We don’t retrieve information or images or words from memory registers. Computers do all of these things, but organisms do not."
This is at best a half-truthy strawman argument. Both our computer technology and the brain's architecture employ different mechanisms by virtue of their underlying implementation. However, the functions performed do converge if you look at what's actually being computed. There are entire fields of both CS and neuro research that are completely based on this overlap.
> "Forgive me for this introduction to computing, but I need to be clear: computers really do operate on symbolic representations of the world. They really store and retrieve. They really process. They really have physical memories. They really are guided in everything they do, without exception, by algorithms.
Humans, on the other hand, do not – never did, never will. "
This is utter bullshit. Humans totally operate on symbolic representations, decades of neuroscience has shown us that. Humans absolutely do store, process, and retrieve information. Humans possess without a doubt physical memories, just because they're not encoded byte-wise doesn't give you an excuse to make these garbage claims.
Humans do operate on symbolic representations, but also on concrete data -- and since you cannot think this data right now, because you can only think (or visualise in your mind) the symbolic representations of that same data -- you end up thinking you don't operate on concrete data.
To add to the fallacy that to think that simply because computations by common computers are done with a bits-and-bytes approach hardware-wise and processes in the brain are not that computers wouldn't be able to express computation that comes very close to processes in the brain:
This is exactly a mapping from one computational calculus (e.g. "brain calculus") to another (e.g. binary logic) with a compiler. While it still might be that the physical processes governing brain functioning somehow elude computational description with digital logic (i.e. such a compiler can not exist. Not sure how this could be the case given the notions of universality by way of Turing machines attached to that), surely this would mean we'd have a new class of computational power on our hands.
And to say that brains are capable of more than Turing-complete (ignoring memory constraints) computation seems hard to believe (see also https://en.wikipedia.org/wiki/Digital_physics). Now how to factor true randomness (if it exists in our universe) into this I don't know, and maybe it doesn't even play a role...
We do. Always have. See my main comment to OP on analog computation and its models that were used for NN's. Hint: One wafer (maybe 40 chips) of analog neurals takes almost 400,000 digital cores to emulate.
> "Forgive me for this introduction to computing, but I need to be clear: computers really do operate on symbolic representations of the world. They really store and retrieve. They really process. They really have physical memories. They really are guided in everything they do, without exception, by algorithms.
Humans, on the other hand, do not – never did, never will."
In addition to neuroscience, going deeper to the atomic level and beyond, humans really do operate on symbolic representations of the world: representations that are stored as states of physical elements. And the algorithm that guides everything we do, would be the laws of physics.
Electronic computers as we have them now are different in many aspects from our brains - right. But they are also similar in many ways and surely we can have some metaphor that would fit both.
What he forgets is that information processor is a metaphor also in respect to the machines we have on our desks. They don't really process information - they just route some electrons around. But metaphors are useful.
Fascinating how somebody can say nothing at all with so many words and give the impression he has a clue. He doesn't seem to know how computers or brains work. For example in the baseball catching story, there is no reason why a computer/robot shouldn't be able to use the same heuristic as a human. ("to catch the ball, the player simply needs to keep moving in a way that keeps the ball in a constant visual relationship with respect to home plate and the surrounding scenery" - why should that be incompatible with information processing?)
There's he's talking more about paradigms that require or oppose mental representations that simulate the motion of a ball. The point there is that it's unnecessary to have an internal mental representation simulating the motion of the ball in order to catch it.
That's a funny way to claim brains are not like computers then. After all the usual argument is that computers have no internal representation of anything.
Why would anybody demand that there has to be an internal mental representation of a ball to catch it?
Right. A brain is like a computer, so far as that is a useful model for discovery. A brain is not like a conventional "computer", so far as accepting this model precludes deeper understanding of brain functions that do not fit the model very well.
Then how come that when I see your comment, my brain knows what letter each symbol represents, and knows what each word means, and can construe a meaning out of the sentence?
Indeed it does. If not, how then can you, "recall" the names of your family upon seeing their faces? You've stored a representation of each face, you've stored their names, and you retrieve that information to maintain the relationship.
pattern recognition. you see a face, and the visual stimulus refires the same set of neurons, which then fire additional neurons, creating a chain that eventually fires off the set that is connected with the sound of that face. This is a pattern of neuron activity, and its not the same as retrieval.
You're just describing a different way to physically distribute the bits. From a mathematical standpoint it's still very clear that information-theoretic bits are going in and coming back out again.
Or to put it another way, if you really think that isn't computing, you need to argue that this new piece of hardware also isn't computing:
ah, no, its not just twiddling bits. You can make analogies to that if it makes it easier to describe a process, but all analogies break down. One may create a mathematical model of the processes but unless that model mimics and predicts the biology so closely as to be indistinguishable from the reality, its still just a model.
Your second assertion is simply wrong. Asserting that what the brain does isn't the same as what a computer does simply doesn't imply that a computer designed to mimic some aspects of biological neural nets is not a computer.
This kind of phrasing implies that you aren't hearing what I'm saying. You're still picturing physical bits that can be twiddled. I'm not making an analogy to any physical bits at all, I'm not even making an analogy.
I'm talking about bits in the information-theoretic sense. If I can send a signal to a person and as a result that person can do better than random at picking an intended symbol out of a set of symbols, then bits of information were conveyed.
If the person can do the same thing at a later point in time, then bits of information were also stored.
No analogies are required, this is literally the definition of "information" and "bits" since 1948.
I'm hearing what you're saying, and if you want to take the broadest possible definition of a computer, then sure, the human brain is a computer. So is a protractor. Shadows on the ground could be used to "compute" the integration of a curve. But its pretty clear that this isn't the issue at hand in the OP.
You've just described a way go store, process, and/or retrieve information. A lossy and generative one. We've modelled similar ones on both digital and analog machines.
It not being a conventional implementation doesn't mean what it's doing isn't computation.
That's a pretty broad definition of computer, even moreso if you're going to claim that the way the human brain arrives at an answer is "specific computation". Moreover, its clearly not the definition used by the author of the article.
The author screwed up by considering only digital computers. You keep ignoring addressing my main counterclaim that there's multiple models of computation, the brain matches one pretty closely, and so it's likely computing and/or a computer.
The evidence I presented of alternative models of computation, neurons, and implementations in those models is here:
"The information processing (IP) metaphor of human intelligence now dominates human thinking, both on the street and in the sciences. ...But the IP metaphor is, after all, just another metaphor – a story we tell to make sense of something we don’t actually understand. And like all the metaphors that preceded it, it will certainly be cast aside at some point – either replaced by another metaphor or, in the end, replaced by actual knowledge. ...the IP metaphor is ‘sticky’. It encumbers our thinking with language and ideas that are so powerful we have trouble thinking around them. ...The idea, advanced by several scientists, that specific memories are somehow stored in individual neurons is preposterous...no one really has the slightest idea how the brain changes after we have learned to sing a song or recite a poem. But neither the song nor the poem has been ‘stored’ in it. The brain has simply changed in an orderly way that now allows us to sing the song or recite the poem under certain conditions. ...The mainstream view is that we, like computers, make sense of the world by performing computations on mental representations of it, but Chemero and others describe another way of understanding intelligent behaviour – as a direct interaction between organisms and their world."
I'm looking up Anthony Chemero's book "Radical Embodied Cognitive Science", and the first sentence of the preface is:
"Jerry Fodor is my favorite philosopher.
I think that Jerry Fodor is wrong about nearly everything.
...My goal is that this book is for non-representational, embodied, ecological psychology what Fodor’s The Language of Thought (1975) was for rationalist, computational psychology."
Jerry Fodor himself was fond of saying, of his ideas with Ernie Lepore, "Absolutely no one agrees with us, which leads me to believe we might be right."
I was studying Neural Networks in grad school (advisor was statistician from Bell Labs) at Rutgers and took a bunch of classes with Jerry, so I had these debates on a daily basis.
Unless you summarize Chemero's critique, though, I can't really respond to it.
Fodor didn't claim that connectionist models couldn't encode symbolic manipulation, just that the pertinent activity from the perspective of "thought" is symbolic manipulation. So he (I believe) would have said, maybe the connectionist can explain it or maybe he can't and who cares.
He did care that "concepts" were not statistical entities. They were "atomic" and basically tokens for the language of thought. So, Jerry argued, the concept of "Lion" could not be complex i.e. composed of cat, claws, teeth etc.
I posted a link and very brief summary elsewhere here. https://news.ycombinator.com/item?id=11730489
He discusses Fodor on p. 26 as part of a critique of conceptual/a priori (Hegelian) arguments.
I don't consider myself either for or against Fodor's argument but I think the summary does great injustice to his arguments.
Fodor does claim that, for what he describes as language, systematicity and compositionality are essential features. However, the "evidence" he cites isn't from a study. It is primarily from facts about language.
To use one of his favorite examples, take these sentences:
The cat ate the rat.
The rat ate the cat.
If you understand sentence 1, you can understand sentence 2, and furthermore, the words "cat", "ate" and "rat" mean the same thing.
He takes those facts to be uncontroversial, and he says that that is what he means by systematicity and compositionality.
This "ability comes in clusters" bit is very confusing, and I am not sure what he means by it.
Fodor doesn't care that connectionists don't have good models for symbolic manipulation. He says that connectionists models are only good in so far as they reduce to symbolic manipulation because symbolic manipulation are the only models we have that demonstrate compositionality and systematicity.
> He takes those facts to be uncontroversial, and he says that that is what he means by systematicity and compositionality.
Right, but Chemero's point is that that premise is not so empirically grounded; it is an a priori assumption.
I am not familiar with this literature, but it's ultimately the same point that he makes against Chomsky's poverty of the stimulus argument (the literature on which I know much better): that it's not an empirically grounded premise, and the evidence for such an a priori argument is weak.
He has a very limited definition of a "computer". His description is how modern computers work. But that's not strictly what a computer could be.
When people compare a computer to a brain. They are not saying it's like a modern pc. They are saying it like a computer in a loose sense. A lot of people don't get that, they think were comparing to the thing on desk. A computer can mean lots of things with many different approaches.
For example
"computers do store exact copies of data" - They don't have to? Just our current implementation does.
Conceptual metaphors lead you astray when you take them too far. You can note some similarities these have, but the author cites lots of examples of people assuming that human brains store, retrieve, and process information just in the way that PCs do.
But that's expanding the definition to "Arbitrary processing architecture we haven't even invented yet which really could simulate a human brain, if only we knew what it was and how to build it - which we don't, but that's just an engineering problem."
Anyway, before we stray too far from the point I was hoping to make, I'll claim that when most people use the word "compute" they mean a particular task performed at the behest of a human being. This sort of definition is problematic if we're ever to attempt to build an artificial brain or to encounter intelligent alien life radically different from our own.
It all falls back to the problem of agency and the philosophical concept of the self.
BTW, I don't believe in free will. You mentioned earlier that there needs to be some magic somewhere and I don't think there is magic. Occam's razor and all that...
Fire is a process that converts chemical inputs into outputs, producing light and heat. It may be involve simpler reactions than protein synthesis but why does that matter?
It's definitely not arbitrary. We have solid mathematical definitions of computing that are not tied to any particular implementation.
Saying "the brain is not a computer" is a shorthand for "the brain is not Turing equivalent".
Now, that could be true. But if it is, it would be the first time anybody has found a physical system in our universe that can't be simulated by a Turing machine. It seems like quite a stretch.
It also never gets into whether the brain is an exception to our laws of physics; if it is not, then it's trivially computable because the laws of physics are. If you're going to argue the brain is not a computer, you need to give plausible reasons for thinking the laws of physics are incomplete (which is what Penrose does, for example).
Any quantum randomness in the brain can be simulated because we know how to generate quantum randomness, then just feed that into a deterministic physics emulator.
As a matter of fact, many computers do not store exact copies of data. The data may be rearranged or compressed on many different levels. The data may be stored in such a way that an exact copy can be retrieved, but it is not necessarily stored as an exact copy.
Moreover, if you include the various checksum algorithms from different vendors as part of "storing", then even if you perform a bit-for-bit copy between different disks, they are not stored exactly the same.
This bit bothered me, on Epstein's Information Processing metaphor:
> The faulty logic of the IP metaphor is easy enough to state. It is based on a faulty syllogism – one with two reasonable premises and a faulty conclusion. Reasonable premise #1: all computers are capable of behaving intelligently. Reasonable premise #2: all computers are information processors. Faulty conclusion: all entities that are capable of behaving intelligently are information processors.
Premise 1, in my reading, is not reasonable. It would be fallacious to assert that all computers are capable of "behaving intelligently", because we don't have a definition for intelligence, let alone a "universal" intelligence that would be consistent between things, or in any case how an individual thing's intelligence would be tested.
The syllogism is the core of the author's contrarian argument. If we can't prove Premise #1 from the preceding syllogism, then the core argument of this essay does seem to lose its legs.
Really, a single viewpoint/facet/argument about the brain-as-a-computer metaphor should undoubtedly be insufficient.
More useful would be a set of arguments that compare or contrast how a computer and a human brain work. We can use these to coalesce an understanding of how close the metaphor is to reality.
How do the two receive information? How do the two store information, recall information, delete information, update stored processes, etc? All of these perspectives begin to build a whole-picture of the relationship, which would seem more useful that trying to boil it down to a single statement.
I think the author needs to revisit his basic assumptions and walk through the argument again, because I don't think what's laid out in the essay actually supports his conclusions, so confidently espoused in the introduction.
just because our brain is not at all like our current 'computers' that we have created architecturally speaking does not mean it is not a computer. Our brains calculate and store and retrieve information, just not to the near-perfect extent that our 'normal' computers do.
I'm a PhD student who studies this stuff. This article is, quite simply, poorly argued.
Most importantly, there's nothing in here that directly argues against the information processing metaphor. The author gives a bad argument that he thinks lies behind the metaphor and shows why that argument is bad. But a) I don't recognize this argument as what motivates the metaphor and b) to show that one argument for a conclusion fails is not to show that the conclusion is false.
The author often points to differences between us and actual computers. No one who employs the information processing metaphor is claiming that we are identical to human-made computers. Rather, the claim is that there's some abstract sense of 'information processing' under which both human brains and computers are implementations. In order for both of those things to be implementations, they need not do so with the exact same kinds of mechanisms, nor must they have the exact same kinds of abilities. (This is why I find the discussion of the dollar drawing case so strange - no one is claiming that we store visual representations of objects in the way that an actual human-made computer does.)
When the author writes:
"To catch the ball, the player simply needs to keep moving in a way that keeps the ball in a constant visual relationship with respect to home plate and the surrounding scenery (technically, in a ‘linear optical trajectory’). This might sound complicated, but it is actually incredibly simple, and completely free of computations, representations and algorithms."
What he describes is not a non-algorithm. Insofar as it's a procedure that takes in certain inputs and follows a series of steps in order to achieve some goal - it just is an algorithm, albeit a somewhat simple one.
More importantly, the author seems to misunderstand what is meant when researchers say that the brain 'runs' an algorithm. Of course you don't consciously crunch numbers when your visual system is chugging away, trying to analyze and sort through the...data...it's getting from the retina. But the lack of conscious computation is not evidence for the complete lack of computation.
There are all sorts of legitimate criticisms of cognitive science - and the author discusses some of these at the end of the piece without really understanding/explaining what's going on behind them. But the author says nothing convincing that it's the failure of the information processing metaphor that explains the limitations/failures of cognitive science.
In fact several people in this thread have explicitly compared human visual memory to lossy compression of images in a computer system. That's his main point, about the metaphor leading people astray.
Understood in the right way, there's nothing wring with that comparison.
Certainly, people misuse/misunderstand the information-processing metaphor/claim. (Though the people who do this tend not to be cognitjve scientists.) But that's not to say that the metaphor is complete garbage.
The vast majority of the posts here are having trouble loking beyond it. That suggests to me that the metaphor is becoming more problematic than useful, at least among people who understand digital technology but who are not cognitive scientists.
My comments from yesterday's thread in /r/Neuropsychology:
While I understand the frustration with the whole Kurzweil camp, this article reads like it was written by an angry high schooler. It also throws the baby out with the bathwater, in that there are clearly valuable analogies to be drawn from computing, as others have mentioned in this thread. My two biggest disagreements:
- "Your brain does not process information": This statement is too broad. How do I do mental math?
- "Memory is not encoded in neurons [as evidenced by a crude drawing of a dollar bill]": Where then does the crude drawing come from?
This article is filled with falsehoods, and poorly reasoned/incorrect arguments.
In particular, we can bat it away by citing the fact there are humans who can recite pi to a large number of decimal places (proving, specifically, that they can store and retrieve digital data). And there are humans who can do long multiplication in their head, by following a series of procedures. Also, humans can store, retrieve, and communicate - with near perfect fidelity - image data (http://www.dailymail.co.uk/news/article-1223790/Autistic-art...)
What the specific molecular structure of the brain's representation of the experience and memory of Beethoven's 5th is almost certainly not stored in a single neuron, this hardly presents talented musicians from playing the 5th from memory.
I'm not convinced by your points. Savants are exceptionally uncommon, and there's no evidence most people can learn the skills they have. Many savants are famously bad at every day human skills, so clearly there's a trade-off - at best.
Storing and operating on numbers with arbitrary precision is a completely trivial operation for all but the oldest computers. But the abilities most humans find trivial - exploring an arbitrary environment by body movement (without falling over), throwing and catching things, playing sports, using tools creatively, reproducing and maintaining relationships, communicating using complex natural languages - are huge engineering problems in the digital space, and most aren't anywhere close to being solved definitively.
So let's ask again - how many of these problems can be solved using Turing complete digital systems?
I don't think anyone can honestly say "All of them." Given the state of the art, a more realistic answer is "We just don't know yet."
As others have commented, the author doesn't seem to understand that computers as Information Processors is also a metaphor. Computers just shuffle electric signals around according to the properties of their circuits. Software is just an abstract way of referring to electricity flowing in a certain way inside the computer.
My knowledge of how computers work is fairly shallow and my knowledge of neuroscience is basically none. With that caveat: this answer https://www.quora.com/Is-the-human-brain-analog-or-digital best fits my biases/intuitions. TLDR: The brain has a digital aspect -- neurons fire and send a signal or they do not -- and an analog aspect -- whether or not a neuron fires depends on the chemical(?) conditions in which it's embedded and inside the cell.
This makes sense to me. That being said, I'm not sure whether I actually disagree with the author. If anyone is trying to find the brain's equivalent of a CPU, that's a fool's errand. It also seems likely that digitizing a brain is not possible, certainly not feasible. Digitizing analog systems is always(?) lossy -- the lossiness just doesn't matter with things like music due to the limitations in human hearing.
This doesn't mean we can't create artificial brains, it just means that they can't be digital machines.
My personal, bad, metaphor for memories is that they work somewhat like linked lists. It's easy enough to recite a poem start to finish. Harder to recite it if you start in the middle. Really hard to recite it backwards. Is this true? Who knows. Does it tell us anything about the underlying mechanisms? Not really.
My the article is misargued mush. It's hard to analyse all 4000 words of it but to pick on a few points:
>But here is what we are not born with: information, data, rules, software, knowledge, lexicons, representations, algorithms, programs, models, memories, images, processors, subroutines, encoders, decoders, symbols, or buffers – design elements that allow digital computers to behave somewhat intelligently. Not only are we not born with such things, we also don’t develop them – ever.
I have several memories.
>cognitive psychologists will never find a copy of Beethoven’s 5th Symphony in the brain
We can build artificial neural networks at the moment to recognise faces and no doubt if you fed them the right inputs, to recognise Beethoven and probably tell you which symphony was playing. You would also not 'find a copy' of the 5th in the neural network. It is likely that the human network of neurons works in a similar manner to the artificial neural network with the learnings stored in modifications to synapses and changes in memory values respectively. I mention this rather obvious stuff because the author goes on to suggest:
>Meanwhile, vast sums of money are being raised for brain research, based in some cases on faulty ideas and promises that cannot be kept
On the basis of the above kind of semi arguments. The fact that the Human Brain Project may be a poor use of research funds is kind of a different issue.
>I challenged researchers there to account for intelligent human behaviour without reference to any aspect of the IP metaphor.
If you think of anything we normally regard as intelligence such as playing chess it involves taking in some information such as where the pieces are and then doing something with it. How that is supposed to prove his point is a loss to me.
etc and on for dozens of other wrong implications and twisted logic. Life's too short...
I found it odd how he noted rooting and nursing instincts in infants, then said that we aren't born with rules or software. That seems self-contradictory.
Well, yes, but he's saying that "rules" and "software" are incorrect metaphors, and that they are a way of saying it wrong. I think that's an important distinction.
What strikes me in the section of the article with the six metaphors is that each one is "true" at a certain level of abstraction, and as time progresses, the abstraction gets thinner and thinner and closer to reality.
The author's claims that I have the biggest problem with are that brains don't store or process information. We clearly do. Our behavior depends at least partly on past experience and our perceptions of current circumstances. When I remember something, do I assert the read and address lines on a NAND chip and latch the data into a register? No, certainly not. Do I trace a weighted graph of neural connections forming a fuzzy cloud of meaning? At the least, that's closer to what I'm doing, and I'd still classify it as information storage and retrieval.
The author doesn't seem like they're attacking the imprecision of a metaphor. They seem like they're rejecting the "brain as a computer" metaphor outright.
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[ 2.6 ms ] story [ 226 ms ] thread- The brain is more fuzzy, but it still stores the link between the smell of roses and the look of roses. Just as a probability, like a Bayes network. And you will fall for Illusions, just like a Bayes network can be wrong ("for a second I thought this was..." and than more information from the senses falsifies/corrects the probabilities).
- The brain is imperfect in reading from memory, but it still does. It just uses really good, lossy compression. It's loosing much detail, but often filling holes probabilistically. Besides neural nets, in computers this would be: defaults, recovery blocks etc. In part the good compression comes from an additional layer of abstraction, but computers can do this too. A very simple example are the the blurry color layers in jpg.
- We are better at recognizing than recalling, because a highly compressed memory is not enough to recreate the original, but has enough indicators to verify. This us very much like a checksum.
What there is, is the bias of the "hardware". Our brains are not good at deterministic iterations, computers struggle with the complexity of forming wisdom and fuzziness and feedback does not come naturally to them either. But in principle, we are both turing complete or something :)
Of course a mere year ago the fact that computers can't get good moves in Go was an argument. And all the arguments that came before that, voice recognition, reading, chess, games, even counting itself at one point. Of all those things that computers/"information processing" couldn't achieve we now know : computers have recognized more spoken text, read more books, letters, envelopes and ... than humans ever will. Computers have played more chess games, and certainly have processed more numbers than humans ever did or ever will. Humans probably still have a mild advantage in amount of Go processing, but it's clear that's not going to last much longer either.
This article takes another approach : because the type of processing that happens in our minds differs "so much" from what we do with computers, they must be fundamentally different. The emphasis lies on the human mind being different : humans don't work like computers, not the opposite. That wouldn't work : because computers do work like humans. That's why we build them, and use them. Computers analyse stocks, sell apples and cars and home insurance, they mail letters, they work out what a business should schedule tomorrow, they move their arms to glue soles onto shoes, ...
One might also analyse why computers are working so very differently. Why Von Neumann ? Well, because we don't really know ahead of time what we want computers to do, and even when we do, we want the ability to change it later. We want computers, to a large extent, and maybe even to 100%, to work like humans do, but we can't do that. As illustrated above, we get closer every year. Computers simulate other machines, that's what they do. So what you should compare is not instruction sets versus neurons, but neural network models those instruction sets simulate with biological neurons.
And then the differences melt away. Not fully. Not yet. We don't know how. Not fully. Not yet.
But more every year.
To use computers as a simile is not so strange.
However, what we still lack completely is any kind of model for autonomy, i.e. how the brain decides what to "compute".
I mean shit, if I judge the distance between two points, how can it not be said that I have collected sensory data and computed the result?
All of his examples were pedantic or irrelevant.
http://cdn.theatlantic.com/assets/media/img/posts/computer_w...
Let's call it "ipython before computers", or "excel before computers" if you must.
In order to make any point remotely like this, he'd have to go talk to some actual neuroscientists, which he very plainly didn't.
http://yosefk.com/blog/ai-problems.html
"We don't build machines in order to raise them and love them; we build them to get work done.
If the thing is even remotely close to "intelligent", you can no longer issue commands; you must explain yourself and ask for something and then it will misunderstand you. Normal for a person, pretty shitty for a machine. Humans have the sacred right to make mistakes. Machines should be working as designed."
A "child" that requires far less resources will be a product that will be incredibly popular. Not to mention an economic necessity.
And I would even say : 100 billion "small" AIs (scale vaguely comparable to a human mind) is a far preferable situation to one big AI. Both from a survivability standpoint and from an "oh my God it'll kill us all" standpoint.
> "We don't build machines in order to raise them and love them; we build them to get work done.
I would even say, if it's at all possible we'll do just that in the next 10-15 years. If we don't get advanced enough AI, perhaps 20-25 years.
Not a doubt in my mind.
(Except for Japanese of course. Excluding them from this question)
Seriously, fertility will become no issue if we prolong fertile period of our lives. Imagine having one kid at thirty, and another one at sixty.
The problem does not tend to be that it's physically impossible to get a child.
Given the author's background, I'd put money on the idea that this is the result of years of frustration at having his life's work dismissively reduced by casual observers to something like "yeah, it's basically a computer" and thinking they therefore understand all the intricacies of the human brain. I can see how that might grate on a person in his field and trigger a response like this.
We know that the brain uses signals, and that these signals are composed of codes. We know that to interpret the world, certain information processing must take place. We are learning more about the exact nature of this processing, more about how neurons and even other fundamentals of the body code information and contribute to processing (e.g. chemical processes), but they definitely process information. We even know some of the codes.
On the other hand, if the author wants to argue about the nature of what is information, what is processing.. he's going to have a steep hill to climb.
https://en.wikipedia.org/wiki/Neural_coding
https://en.wikipedia.org/wiki/Neural_decoding
From this we can often find things like:
- frequency of impulses increases as stimulus increases
- different numbers of neurons in a similar area fire simultaneously
Things like that. The wikipedia articles linked by wickedagain contain a good summary. I won't link specific sources, since there are thousands, but here's one for instance:
http://jn.physiology.org/content/85/4/1561
There in fig 6 for example you can see that the frequency of nerve firing increases in the tibial nerve as heat is applied to the paw. (Yes, a lot of information comes from horrible animal studies. It's part of the reason I didn't continue in this domain of work -- although rest assured, this technique is possible with humans, without harm.)
So, do impulses in the perceptual nervous system reflect how brains work, how we think? It's hard to say for sure, but it's clear that information is coded according to certain possibilities related to how neurons work, and this information must be combined and processed somehow to create what we call perceptions. Is it such a stretch to imagine that these perceptions become their own codes, abstract reductions of correlations of perceptual information, that are evaluated, compared, and combined in the much, much more nerve-dense central cortex to produce what we call "thought"?
A further frustration might be with computers themselves. I don't see why an introduction/exposition to computing should be something that needs pardon.
The same thing could be said about 'intelligence'. Current definitions of intelligence are not abstract definitions(even though the word itself seems like some abstract term, similar to calculation, motion etc.), but rather are labels/descriptions of particular human traits. If a more abstract definition was offered, you would see a lot more things in nature 'becoming' intelligent. So, currently we are in a situation where 'intelligence' is defined in terms of human traits(like being able to speak human language, do human mathematics, drive cars etc), but then at the same time we're looking for intelligent aliens. You can't find 'intelligent' aliens if the term intelligence is defined in such a way to only ever apply to humans. It's really a parlor trick.
This is an expression of human desire to feel special - you don't want to be labeled as a computer or cluster of regular matter - rather you are an 'intelligent' soul(a different substance, not a regular matter) made in the image of the most powerful creature in the universe who happens to love you and care about you.
Agreed with the rest of what you wrote, but "intelligence" is more or less uniformly defined as the ability to quickly assimilate and apply information. What we try to measure is the speed, accuracy and complexity of that process. We have tried to measure the same process with dogs, parrots, monkeys, and ravens, and we even use comparable scales (e.g. general opinion is that adult dogs can handle the same mental complexity as toddlers).
You are correct that the tests we use incorporate human traits. But that's as much because we are mainly testing humans as because we use humans as our reference.
What these experiments with animals are designed for is to check which animals can do things in a similar way to humans.
Why are ravens intelligent? Is it because they can quickly process information? No, that is not what experiments are checking. They are labelled as intelligent because they can use tools to unlock their food.
Why are dolphins intelligent? Is it because they process complex information quickly? No, it's because they have large brains and exhibit empathy towards humans plus they seem to be able to communicate with each other.
People don't say "Well, that system can process complex information quickly, therefore it's intelligent". Instead, what you'll hear is "WOW, animal X can use tools, can communicate, organize in groups! They are more intelligent that we thought". Using tools or communicating is just one way of processing information. There are many other ways. For example, an animal might not be able to use tools in a cage to unlock their food, but they could be a terrific fighter in the jungle. Fighting in a jungle is a process that demands quick information processing, but those animals are somehow below in intelligence than revens or dogs. That is because people aren't using the definition you've provided.
There is no need to incorporate human traits, because you've already defined the term in a good way. Why do you need humans for reference? You have the definition, you can provide measurement for speed (X per second) and you're good to go. You don't use humans to measure acceleration of objects, so why would you use humans to measure intelligence?- The brain's network is not very well understood. For example, half your body's neurons are in your cerebellum. There people that don't have a cerebellum, and they only seem to walk later, and have balance issues [0]. That is half of all your neurons, and until you do a scan, people can't tell you are missing them. Alternatively, we have Henry Molaison (known in literature as HM), who could not remember a thing from after his surgery to save his life. All the surgeons took was his hippocampus (and some other stuff) back in 1953, which we then found out was SUPER important for memory [1]. He lived to be 82 and died in 2008, incidentally. Suffice to say, the neurons, their local network, and the long range network (aka, your whole body) are all very important in terms of how it all works. You can take out a ton, and not loose really anything, or you can take out some special ones and never remember a thing again. The brain is not 'fuzzy' and really 'fuzzy' all at the same time. It's like lumping all of China's politics into just their Chairman's ideas; you loose any sense of what is going on.
-The brain's recall system is also not well known. As with HM's life, you take out this special part, and it all goes to shit. However, when HM sang or played music, he could do an entire song or piece, even if it was Indagardadavida's length. Also, he remembered shocks to his hand when a surgeon put a joke buzzer in one day; he was hesitant to shake the next day. Our memory is not in any way good or lossy. Look at PTSD victims, they remember it ALL. Typically, it comes down to the motivations of the person. If you have to remember for the future, like an important fact for a test, or the sound a wolf makes right before it leaps onto you, then you will remember it very well. If you don't need to remember, then you typically do not. Again though, the brain is not well understood and we all have experienced exceptions to this.
-Some people are better at recognizing, some are better at recalling, and we don't know why. People that are face blind [2] are really bad at remembering faces; Brad Pitt says that he is face blind. Some people are really good with faces and really bad with names, some are the opposite. Some are synesthetes [3] and will recall equations or speeches by the taste that they experience when doing it. Some people are savants and can recall an entire phonebook and then draw it, nearly as a cc, from memory [4]. Memory is a fascinating subject and whenever you think you know what is going on, something new opos up and kills the theory.
-Our brains can be very good at deterministic calculations. Any major league ballplayer is very good in the outfield (the D-backs excepted this year) and can very accurately catch a ball hit from 100s of feet away. They may not be good with math, but some of them are much better than any computer [5].
The brain is not well understood at this time. Calling it a computer is obvious nonsense, but it's a good working theory to approach from, especially considering we have no other real ideas.
[0] http://www.iflscience.com/brain/24-year-old-woman-born-witho...
[1]https://en.wikipedia.org/wiki/Henry_Molaison
[2]https://en.wikipedia.org/wiki/Prosopagnosia
[3] https://en.wikipedia.org/wiki/Synesthesia
[4]www.neatorama.com/2008/09/05/10-most-fascinating-savants-in-the-world/
[5]
It's just not computer in the way you think a computer works.
In The New York Times was February 3, 1853, an obituary stated: "Mr. Walker was widely known as an accomplished Astronomer and a skillful Computer."
So to claim that the very thing which enables us to be a computer, is not a computer, might simply be short-sighted or trying to be absurd.
> "But here is what we are not born with: information, data, rules, software, knowledge, lexicons, representations, algorithms, programs, models, memories, images, processors, subroutines, encoders, decoders, symbols, or buffers"
We are born with most (if not) all of these things, and we develop more of them as we grow and learn. Sure, the nomenclature here was chosen for ridicule, but functionally those elements are present.
The brain is not a magical pudding that works in a completely occult and mysterious manner. While we do have a ways to go in deciphering the minutiae of its architecture and operation, the article engages in assertions that run completely counter to neurobiological facts we have already learned:
> "We don’t store words or the rules that tell us how to manipulate them. We don’t create representations of visual stimuli, store them in a short-term memory buffer, and then transfer the representation into a long-term memory device. We don’t retrieve information or images or words from memory registers. Computers do all of these things, but organisms do not."
This is at best a half-truthy strawman argument. Both our computer technology and the brain's architecture employ different mechanisms by virtue of their underlying implementation. However, the functions performed do converge if you look at what's actually being computed. There are entire fields of both CS and neuro research that are completely based on this overlap.
> "Forgive me for this introduction to computing, but I need to be clear: computers really do operate on symbolic representations of the world. They really store and retrieve. They really process. They really have physical memories. They really are guided in everything they do, without exception, by algorithms.
Humans, on the other hand, do not – never did, never will. "
This is utter bullshit. Humans totally operate on symbolic representations, decades of neuroscience has shown us that. Humans absolutely do store, process, and retrieve information. Humans possess without a doubt physical memories, just because they're not encoded byte-wise doesn't give you an excuse to make these garbage claims.
This is exactly a mapping from one computational calculus (e.g. "brain calculus") to another (e.g. binary logic) with a compiler. While it still might be that the physical processes governing brain functioning somehow elude computational description with digital logic (i.e. such a compiler can not exist. Not sure how this could be the case given the notions of universality by way of Turing machines attached to that), surely this would mean we'd have a new class of computational power on our hands.
And to say that brains are capable of more than Turing-complete (ignoring memory constraints) computation seems hard to believe (see also https://en.wikipedia.org/wiki/Digital_physics). Now how to factor true randomness (if it exists in our universe) into this I don't know, and maybe it doesn't even play a role...
Humans, on the other hand, do not – never did, never will."
In addition to neuroscience, going deeper to the atomic level and beyond, humans really do operate on symbolic representations of the world: representations that are stored as states of physical elements. And the algorithm that guides everything we do, would be the laws of physics.
What he forgets is that information processor is a metaphor also in respect to the machines we have on our desks. They don't really process information - they just route some electrons around. But metaphors are useful.
Why would anybody demand that there has to be an internal mental representation of a ball to catch it?
It's a computer more advanced by evolution than we've built through our understanding of science.
Or to put it another way, if you really think that isn't computing, you need to argue that this new piece of hardware also isn't computing:
https://cloudplatform.googleblog.com/2016/05/Google-supercha...
Your second assertion is simply wrong. Asserting that what the brain does isn't the same as what a computer does simply doesn't imply that a computer designed to mimic some aspects of biological neural nets is not a computer.
This kind of phrasing implies that you aren't hearing what I'm saying. You're still picturing physical bits that can be twiddled. I'm not making an analogy to any physical bits at all, I'm not even making an analogy.
I'm talking about bits in the information-theoretic sense. If I can send a signal to a person and as a result that person can do better than random at picking an intended symbol out of a set of symbols, then bits of information were conveyed.
If the person can do the same thing at a later point in time, then bits of information were also stored.
No analogies are required, this is literally the definition of "information" and "bits" since 1948.
It not being a conventional implementation doesn't mean what it's doing isn't computation.
The evidence I presented of alternative models of computation, neurons, and implementations in those models is here:
https://news.ycombinator.com/item?id=11731697
RTWT.
1. The computational theory of mind is the only remotely plausible theory of mind.
2. A remotely plausible theory is better than none at all.
We know we literally process symbols because I can literally read a book, and I can literally write something down.
"Jerry Fodor is my favorite philosopher. I think that Jerry Fodor is wrong about nearly everything.
...My goal is that this book is for non-representational, embodied, ecological psychology what Fodor’s The Language of Thought (1975) was for rationalist, computational psychology."
Looks like there's little skepticism about the power of neural networks here, even if some of the arguments are framed in terms of computationalism. https://en.wikipedia.org/wiki/Connectionism#Connectionism_vs...
Unless you summarize Chemero's critique, though, I can't really respond to it.
Fodor didn't claim that connectionist models couldn't encode symbolic manipulation, just that the pertinent activity from the perspective of "thought" is symbolic manipulation. So he (I believe) would have said, maybe the connectionist can explain it or maybe he can't and who cares.
He did care that "concepts" were not statistical entities. They were "atomic" and basically tokens for the language of thought. So, Jerry argued, the concept of "Lion" could not be complex i.e. composed of cat, claws, teeth etc.
I don't consider myself either for or against Fodor's argument but I think the summary does great injustice to his arguments.
Fodor does claim that, for what he describes as language, systematicity and compositionality are essential features. However, the "evidence" he cites isn't from a study. It is primarily from facts about language.
To use one of his favorite examples, take these sentences:
If you understand sentence 1, you can understand sentence 2, and furthermore, the words "cat", "ate" and "rat" mean the same thing.He takes those facts to be uncontroversial, and he says that that is what he means by systematicity and compositionality.
This "ability comes in clusters" bit is very confusing, and I am not sure what he means by it.
Fodor doesn't care that connectionists don't have good models for symbolic manipulation. He says that connectionists models are only good in so far as they reduce to symbolic manipulation because symbolic manipulation are the only models we have that demonstrate compositionality and systematicity.
Right, but Chemero's point is that that premise is not so empirically grounded; it is an a priori assumption.
I am not familiar with this literature, but it's ultimately the same point that he makes against Chomsky's poverty of the stimulus argument (the literature on which I know much better): that it's not an empirically grounded premise, and the evidence for such an a priori argument is weak.
When people compare a computer to a brain. They are not saying it's like a modern pc. They are saying it like a computer in a loose sense. A lot of people don't get that, they think were comparing to the thing on desk. A computer can mean lots of things with many different approaches.
For example "computers do store exact copies of data" - They don't have to? Just our current implementation does.
The brain has input, goes through various connections, and you end up with a result.
Anyway, before we stray too far from the point I was hoping to make, I'll claim that when most people use the word "compute" they mean a particular task performed at the behest of a human being. This sort of definition is problematic if we're ever to attempt to build an artificial brain or to encounter intelligent alien life radically different from our own.
It all falls back to the problem of agency and the philosophical concept of the self.
I'd argue genetic code (messenger RNA) is a program and inputting genes and outputting proteins is a form of computation.
BTW, I don't believe in free will. You mentioned earlier that there needs to be some magic somewhere and I don't think there is magic. Occam's razor and all that...
Maybe that's a defining characteristic - complexity.
Saying "the brain is not a computer" is a shorthand for "the brain is not Turing equivalent".
Now, that could be true. But if it is, it would be the first time anybody has found a physical system in our universe that can't be simulated by a Turing machine. It seems like quite a stretch.
Any quantum randomness in the brain can be simulated because we know how to generate quantum randomness, then just feed that into a deterministic physics emulator.
To deny that requires new laws of physics.
Moreover, if you include the various checksum algorithms from different vendors as part of "storing", then even if you perform a bit-for-bit copy between different disks, they are not stored exactly the same.
> The faulty logic of the IP metaphor is easy enough to state. It is based on a faulty syllogism – one with two reasonable premises and a faulty conclusion. Reasonable premise #1: all computers are capable of behaving intelligently. Reasonable premise #2: all computers are information processors. Faulty conclusion: all entities that are capable of behaving intelligently are information processors.
Premise 1, in my reading, is not reasonable. It would be fallacious to assert that all computers are capable of "behaving intelligently", because we don't have a definition for intelligence, let alone a "universal" intelligence that would be consistent between things, or in any case how an individual thing's intelligence would be tested.
The syllogism is the core of the author's contrarian argument. If we can't prove Premise #1 from the preceding syllogism, then the core argument of this essay does seem to lose its legs.
Really, a single viewpoint/facet/argument about the brain-as-a-computer metaphor should undoubtedly be insufficient.
More useful would be a set of arguments that compare or contrast how a computer and a human brain work. We can use these to coalesce an understanding of how close the metaphor is to reality.
How do the two receive information? How do the two store information, recall information, delete information, update stored processes, etc? All of these perspectives begin to build a whole-picture of the relationship, which would seem more useful that trying to boil it down to a single statement.
I think the author needs to revisit his basic assumptions and walk through the argument again, because I don't think what's laid out in the essay actually supports his conclusions, so confidently espoused in the introduction.
Most importantly, there's nothing in here that directly argues against the information processing metaphor. The author gives a bad argument that he thinks lies behind the metaphor and shows why that argument is bad. But a) I don't recognize this argument as what motivates the metaphor and b) to show that one argument for a conclusion fails is not to show that the conclusion is false.
The author often points to differences between us and actual computers. No one who employs the information processing metaphor is claiming that we are identical to human-made computers. Rather, the claim is that there's some abstract sense of 'information processing' under which both human brains and computers are implementations. In order for both of those things to be implementations, they need not do so with the exact same kinds of mechanisms, nor must they have the exact same kinds of abilities. (This is why I find the discussion of the dollar drawing case so strange - no one is claiming that we store visual representations of objects in the way that an actual human-made computer does.)
When the author writes:
"To catch the ball, the player simply needs to keep moving in a way that keeps the ball in a constant visual relationship with respect to home plate and the surrounding scenery (technically, in a ‘linear optical trajectory’). This might sound complicated, but it is actually incredibly simple, and completely free of computations, representations and algorithms."
What he describes is not a non-algorithm. Insofar as it's a procedure that takes in certain inputs and follows a series of steps in order to achieve some goal - it just is an algorithm, albeit a somewhat simple one.
More importantly, the author seems to misunderstand what is meant when researchers say that the brain 'runs' an algorithm. Of course you don't consciously crunch numbers when your visual system is chugging away, trying to analyze and sort through the...data...it's getting from the retina. But the lack of conscious computation is not evidence for the complete lack of computation.
There are all sorts of legitimate criticisms of cognitive science - and the author discusses some of these at the end of the piece without really understanding/explaining what's going on behind them. But the author says nothing convincing that it's the failure of the information processing metaphor that explains the limitations/failures of cognitive science.
Certainly, people misuse/misunderstand the information-processing metaphor/claim. (Though the people who do this tend not to be cognitjve scientists.) But that's not to say that the metaphor is complete garbage.
While I understand the frustration with the whole Kurzweil camp, this article reads like it was written by an angry high schooler. It also throws the baby out with the bathwater, in that there are clearly valuable analogies to be drawn from computing, as others have mentioned in this thread. My two biggest disagreements:
- "Your brain does not process information": This statement is too broad. How do I do mental math?
- "Memory is not encoded in neurons [as evidenced by a crude drawing of a dollar bill]": Where then does the crude drawing come from?
Thank you for making this point. I am completely unable to follow the author's logic
In particular, we can bat it away by citing the fact there are humans who can recite pi to a large number of decimal places (proving, specifically, that they can store and retrieve digital data). And there are humans who can do long multiplication in their head, by following a series of procedures. Also, humans can store, retrieve, and communicate - with near perfect fidelity - image data (http://www.dailymail.co.uk/news/article-1223790/Autistic-art...)
What the specific molecular structure of the brain's representation of the experience and memory of Beethoven's 5th is almost certainly not stored in a single neuron, this hardly presents talented musicians from playing the 5th from memory.
Are all brains Turing complete?
I'm not convinced by your points. Savants are exceptionally uncommon, and there's no evidence most people can learn the skills they have. Many savants are famously bad at every day human skills, so clearly there's a trade-off - at best.
Storing and operating on numbers with arbitrary precision is a completely trivial operation for all but the oldest computers. But the abilities most humans find trivial - exploring an arbitrary environment by body movement (without falling over), throwing and catching things, playing sports, using tools creatively, reproducing and maintaining relationships, communicating using complex natural languages - are huge engineering problems in the digital space, and most aren't anywhere close to being solved definitively.
So let's ask again - how many of these problems can be solved using Turing complete digital systems?
I don't think anyone can honestly say "All of them." Given the state of the art, a more realistic answer is "We just don't know yet."
My knowledge of how computers work is fairly shallow and my knowledge of neuroscience is basically none. With that caveat: this answer https://www.quora.com/Is-the-human-brain-analog-or-digital best fits my biases/intuitions. TLDR: The brain has a digital aspect -- neurons fire and send a signal or they do not -- and an analog aspect -- whether or not a neuron fires depends on the chemical(?) conditions in which it's embedded and inside the cell.
This makes sense to me. That being said, I'm not sure whether I actually disagree with the author. If anyone is trying to find the brain's equivalent of a CPU, that's a fool's errand. It also seems likely that digitizing a brain is not possible, certainly not feasible. Digitizing analog systems is always(?) lossy -- the lossiness just doesn't matter with things like music due to the limitations in human hearing.
This doesn't mean we can't create artificial brains, it just means that they can't be digital machines.
My personal, bad, metaphor for memories is that they work somewhat like linked lists. It's easy enough to recite a poem start to finish. Harder to recite it if you start in the middle. Really hard to recite it backwards. Is this true? Who knows. Does it tell us anything about the underlying mechanisms? Not really.
>But here is what we are not born with: information, data, rules, software, knowledge, lexicons, representations, algorithms, programs, models, memories, images, processors, subroutines, encoders, decoders, symbols, or buffers – design elements that allow digital computers to behave somewhat intelligently. Not only are we not born with such things, we also don’t develop them – ever.
I have several memories.
>cognitive psychologists will never find a copy of Beethoven’s 5th Symphony in the brain
We can build artificial neural networks at the moment to recognise faces and no doubt if you fed them the right inputs, to recognise Beethoven and probably tell you which symphony was playing. You would also not 'find a copy' of the 5th in the neural network. It is likely that the human network of neurons works in a similar manner to the artificial neural network with the learnings stored in modifications to synapses and changes in memory values respectively. I mention this rather obvious stuff because the author goes on to suggest:
>Meanwhile, vast sums of money are being raised for brain research, based in some cases on faulty ideas and promises that cannot be kept
On the basis of the above kind of semi arguments. The fact that the Human Brain Project may be a poor use of research funds is kind of a different issue.
>I challenged researchers there to account for intelligent human behaviour without reference to any aspect of the IP metaphor.
If you think of anything we normally regard as intelligence such as playing chess it involves taking in some information such as where the pieces are and then doing something with it. How that is supposed to prove his point is a loss to me.
etc and on for dozens of other wrong implications and twisted logic. Life's too short...
(For a kind of counter argument check out the Recurrent Neural Networks and Inceptionism articles https://news.ycombinator.com/item?id=9584325 and https://news.ycombinator.com/item?id=9736598 for how eeriely close the behaviour of artificial neural networks can be to human ones)
What strikes me in the section of the article with the six metaphors is that each one is "true" at a certain level of abstraction, and as time progresses, the abstraction gets thinner and thinner and closer to reality.
The author's claims that I have the biggest problem with are that brains don't store or process information. We clearly do. Our behavior depends at least partly on past experience and our perceptions of current circumstances. When I remember something, do I assert the read and address lines on a NAND chip and latch the data into a register? No, certainly not. Do I trace a weighted graph of neural connections forming a fuzzy cloud of meaning? At the least, that's closer to what I'm doing, and I'd still classify it as information storage and retrieval.
The author doesn't seem like they're attacking the imprecision of a metaphor. They seem like they're rejecting the "brain as a computer" metaphor outright.
https://webcache.googleusercontent.com/search?q=cache:1UZsMv...