Some people consider the brain a computer. Like brain philosopher D. Hofstadter. In a public talk he gave he tried to do anything to show that. Including tackling opponents. But he couldn't convince (that is, me). Hofstadter is a computer scientists also, so maybe it is no wonder he thinks like that. It's his culture and I couldn't stop thinking that he was programmed properly to gave this talk in favor of programmed behavior.

If we look at this subject from a more objective realm, so not like Hofstadter does from the region where computers are programmed on a daily basis, how must we judge this claim? Of course Hofstadter knows a lot about programming and flexibility or infinite self referring loops but if we look at the brain then where is the program installed and how does it operate on data to compute the next state of the brain? If we look at the brain then there is nothing going on that looks even remotely like how a working computer looks. Even when imaging a future supercomputer there is always something (data) computed by a set of computing instructions (program).

Can't we say that processes in the brain just happen, like physical processes in the world just happen without a program they follow? These processes follow natural laws but they are not computed. A particle moving in a force field doesn't compute its next position nor does an external agent. Processes in the brain are internal representations of these processes so they too could evolve without a program. They are based in a neuronal medium (resembling the real world in many aspects even the chaos of lightning flashes and tree or plant roots, as their form shows; how to implement the chaos of a lighning flash in a straight lined chip?) suited to whirl around as the physical processes seen in the world whirl around.

Which is not to say that I can use my brain like a computer. I can compute (my brain can) how a physical process in the brain of someone evolves, though an ultrafast parallel quantum computer would do that job much better and certainly faster.

Thanks to a suggestion made by a user, can we maybe say that the brain is an analog computer?

  • Comments are not for extended discussion; this conversation has been moved to chat.
    – Geoffrey Thomas
    Commented Aug 1, 2021 at 11:02
  • you may have a look at the SEP entry on the computational theory of mind; there seems to be a difference between the idea that the mind is analogous to a computer and the idea that the mind runs a program Commented Aug 1, 2021 at 19:34
  • @FloridusFloridi What is SEP?
    – user53283
    Commented Aug 1, 2021 at 19:50
  • Stanford Encyclopedia Of Philosophy ( sorry I should have written it completely) Commented Aug 1, 2021 at 20:20
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    @FloridusFloridi Thanks for the suggestion. That was some nice reading! The problem is indeed what is meant by computation. I think the brain looks more like an analog computer. In that sense its a computer maybe. If I think about an object, an analogue process is going on in my brain. Thanks for the link again!
    – user53283
    Commented Aug 1, 2021 at 21:40

7 Answers 7


The problem is with the definition of "computer".

Certainly the brain does not conform to any ordinary example of a computer - a kind of man-made machine.

People might observe that somehow there are rules or regularities appearing to govern both brains and computers, but that is true of the whole natural world. One of the tenets of science is that the natural world works regularly and deterministically.

Are brains and computers alike in being objects in the natural world? Yes. But that is really about as far as the commonality goes.

  • I'm not going to down vote, but professional philosophers, such as Searle, concede the brain is a type of computer. "By contrast, most uses of computation in science and ordinary practice deal with concrete computation: computation in physical systems such as computers and brains." - Computation in Physical Systems (SEP) In fact, the Turing Machine formalism was an abstraction of human mathematicians. Originally, the term 'computer' only applied to people, and not machines.
    – J D
    Commented Jun 8, 2023 at 20:10
  • "But perhaps what brains and computers do is fundamentally the same, even if the architecture is different. “What the brain seems to be doing is quite aptly described as information processing,” says Megan Peters, a cognitive scientist at the University of California, Irvine." - Leaving this here for the curious. technologyreview.com/2021/08/25/1030861/is-human-brain-computer
    – J D
    Commented Jun 8, 2023 at 20:11
  • @JD, certainly the brain can compute. We can, after all, do anything a digital computer can do (save more slowly), and they are machines of our own design. "Analog computers" collectively work in more ill-defined ways, and are typically about finding a mechanical or electrical process which works analogously to some physical process. The problem is that, once we are not talking about man-made computers, the definition of computation becomes so wide that the word becomes meaningless (1/2)
    – Steve
    Commented Jun 9, 2023 at 9:30
  • The perceived commonality is essentially reduced to the scientific tenet that the natural world is deterministic and therefore extensively amenable to human analysis. You could go as far as to say the Earth is computing to maintain its spherical shape, in the sense that the whole system is constantly sounded and mass redistributed so as to tend towards spherical shape. But it's a long way from the word "computing" as we know it. And brains too don't work close to any principle of man-made computer devices. Brains aren't computers, except in an exhaustive sense that covers everything. (2/2)
    – Steve
    Commented Jun 9, 2023 at 9:32
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    @JD, I don't mind discussing! But I ask, is there anything alive (let alone a variety of inanimate objects not conventionally understood as computers) which doesn't become a "computer" in your view? In the same way that the word "thing" is what every object is, it seems to me you're using the word "computer" to simply mean what every object does (i.e. a "computer" becomes a synonym for "thing", but referencing a universal aspect of what all things in the real world do).
    – Steve
    Commented Jun 9, 2023 at 12:15

Computers are used as an analogy for the human brain/mind. Analog commuters are arguably a better analogy that digital computers, and (again, arguably) quantum computers might be an even better analogy, seeing the mind as a superposition of various potential states encoded into the physical brain.

But it's merely an analogy, and moreover an analogy framed by and rooted in a distinctly anti-metaphysical, anti-theological empiricist worldview. It's best to restrict ourselves to asking whether it's a useful analogy, because the moment we start wondering whether it's a truth the entire conversation degrades into polemics.

  • Analog is a better analog-y. Makes good sense. Binary doesn't seem to capture reality so well these days.
    – Scott Rowe
    Commented Jun 11, 2023 at 23:38

Can a bird be considered a materialized photo of a bird?

There must be some sort of fallacy about the original mistaken for a derivative. Just as the image in a photo is derived from its original physical object, computers are derived from a human work of logical processing, not the other way around. Computers are made to automate TM-like tasks that people naturally perform, so they can be considered a mechanized calculus and decision-making analogy of the brain. (Which is, among other things, a very narrow subset of what human brains do.)

But when brain is considered to be a computer instead, it is erroneously positioned as a secondary category to the primary category "computer". This leads to a play on words and meanings. Which is a quite ordinary everyday misconception, but hardly contains any solid philosophic thought behind it other than elaborating on superficial similarity.

  • Are you suggesting a claim that the claim that a PC is nothing more than a photo of the brain is equivalent to the claim that PCs and brains fundamentally are organized and behave in similar ways?
    – J D
    Commented Jun 10, 2023 at 14:59
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    @JD I mean that computer can be compared to brain (in a narrow sense), because computer is designed to replace a certain type of routine brain work. But comparing brain to computer reverses the interrelation between the two, as if brain was designed to work like computer.
    – blakkwater
    Commented Jun 10, 2023 at 15:21
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    @JD Well, it seems that I convey my point worse than I expected I can! :) Truth #1: Some people are used to be impressed by trivial similarities between things, and they like to talk about them. Truth #2: Some other people are prone to misinterpret trivial talking as a deep analytical effort that (to their surprise) lacks something crucial... and start arguing!
    – blakkwater
    Commented Jun 10, 2023 at 18:15
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    @JD These are two distinct cognitive models, which (for some reason) are often confused with each other. MY point, is there's NO point to argue in this case. Whoever compares brain to computer, most likely doesn't mean anything serious. Just marks similar properties of random things, finds the discovery amusing, and starts to talk about it. That's it. Simple as hell.
    – blakkwater
    Commented Jun 10, 2023 at 18:15
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    +1 lol You're philosophy is inadequate, but your intelligence exceeds expectations. I see the prima facie force in your claims. Welcome. I hope you stick around and contribute.
    – J D
    Commented Jun 10, 2023 at 18:19

Computers (in the narrow sense, like the laptop I'm typing on right now) are also physical things whose processes "just happen" like the physical processes of the natural world do. They're built out of wires and such, just following the laws of electromagnetism and such, but they can also be described as having input (like what I'm typing now), processing (like how it translates that typing into graphemes on a screen), and output (like displaying it to other people looking at this webpage through their own screens). And same for the brain: It's composed of neurons and such, just following the laws of electromagnetism and such, but can still be described as having input (like sensory perception), processing (translating light waves into visual experiences, or visual experiences into linguistic representations), and output (like saying what you saw). This is obviously a very simplified sketch, which theorists in the computational theory of mind have a lot more to say on. But if you think of the word "computer" as just meaning a thing that receives input, processes it, and produces output, the brain is a computer.

  • Of course move all particles in my brain as described by physics. I dont deny that. But in a computer they also move according to an external program.
    – user53283
    Commented Aug 2, 2021 at 7:09
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    Then a coffee machine is a computer too...
    – user53283
    Commented Aug 2, 2021 at 7:19
  • The point is, how does the processing succeed. In your laptop there is a program that operates on the data. From the outside. Thats not whats happening in the brain.
    – user53283
    Commented Aug 2, 2021 at 7:27
  • Yeah, a coffee machine can be considered a computer, but there's no point in looking at it through that lens because the kind of processing a coffee machine does is more efficiently described on a physical level, rather than in terms of information-processing. The motivation behind the computational theory of mind is the hypothesis that we can better understand the human mind by reverse-engineering it by use of the concepts that we use in the engineering of things (computers in the narrow sense) that we've designed in attempts to replicate some of the human mind's capacities.
    – Dayv87
    Commented Aug 2, 2021 at 7:31
  • What do you mean by reverse engineering the brain?
    – user53283
    Commented Aug 2, 2021 at 7:34

Even when imaging a future supercomputer there is always something (data) computed by a set of computing instructions (program).

Yes, and there will always be a screen, a keyboard and a power cable. Where are those in the brain??? To be serious, having a program and instructions is not philosophically a defining property of a computer, it is incidental, like having a keyboard. Using programs is for our convenience as engineers only.

And note that for artificial neutral network programs, it is fair to say that the process is encoded in the data, not in the program.

Can't we say that processes in the brain just happen, like physical processes in the world just happen without a program they follow?

No, as philosophers we do need to admit human behavior is planned and problem solving, processing data from the environment to produce rational responses. We recognize this is data processing, and it is done in the brain.

That does not imply that a program is involved or that our behavior is programmed. It just means data processing is involved.

However you might think about some programming even in the brain. Like the most basic is the heart beating and breathing. Those just happen automatically. Then you have coughing and sneezing. The blinking of the eye. Even more dramatic, your have sleeping and waking. You have the drives to eat and drink, the need to have sex, even the sexual preference. All those are not matters of choice, though we can suppress them to some degree. But those hint at something like programs that people follow every day, despite other aspects being completely individual and non-program-like. This still does not mean that or brain has a single program, just that there are some parallels and execution pattern structures.


Short Answer

Yes, by most conventional definitions, the human brain is an analog computer with the caveat that there are a range of definitions for 'computer', so it's best to use an abstract one.

Long Answer

Sufficiently Generalized Definition of Computer

Before we tackle the answer in question, let us observe that according to prototype theory which springs from Wittgenstein's notion of family resemblance, it would be silly to bicker over details of definitions of computers that stem from necessary and sufficient definitions for more concrete examples. Computers can be embedded, general purpose, digital, analog, distributed, biological, electromechanical, or even biochemical, as in computations that are performed with nucleic acids. Abstracting from different sorts of computers leads to an idealized definition of a computer that is frequently seen in introductory textbooks on information systems and information technology:

A computer is any system which embodies the information processing cycle.

This is vague and useful as one can get, and very much lends itself to setting up a short ontological razor with the four phases of the information processing cycle: input, storage, processing, and output.

The Watch, an Abacus, and a Cup of Coffee

Given the definition above, what is important is that a system embody all four phases of the information processing system. Let's think about two devices that commonly held to be computers: the watch and the abacus. In the case of a watch, even a mechanical one, all four phases of the information processing cycle are present. First, you have to enter a time. The point of a wrist watch is to keep a number which represents the time of day synchronized with the world. So, a user enters in a reasonable approximation of the current time. This is input, and on a mechanical watch, is often accomplished with a small dial. Now that the time has been entered, it will change at a predetermined rate. If the gears are relatively continuous, then the watch is an analog computer, and if the gears allow for a punctuated smallest transaction, say the transition from 1s discretely to the next, the system is digital. This is the processing aspect of an information system. Of course, the time that is stored/represented by the watch is within the gear structure itself, which is the way the watch stores the current time. Now, that value is visible to the user traditionally with a hour, minute, and second hand, so the face of the watch ultimately allows for output. It might be possible, for example, for the internal mechanism to function correctly and the hands to be damaged. A watch therefore automates a number system to track the passage of time. Time and numbers are abstractions, so ultimately they are forms of information.

An abacus, which is often touted as an example of a computer, is not a computer under this definition. Why? Let's follow the same train of logic. A user certainly can configure an abacus or quipu to represent a number. This would be inputting a number. And at a glance the user could then, days later, take a look at that representation of the number in the physical medium demonstrating that the number has been stored and is capable of output. But where an abacus does not fulfill our definition of the computer is by its inability to automate information processing by having a processing phase. Traditional abaci simply do not transform the informational representation in the same way a watch or a microprocessor is capable of. One often hears the argument that the beads slide, for instance on a frame, and that is processing, but that processing really is not the abacus, but the user of the abacus. In this way, an abacus is more like a pencil and a pad of paper. You can write a number on it, and days later retrieve that number long after you have forgotten it, but unlike a mechanical watch or a digital CPU, there will be no change of state without the user. An abacus no more computes than does a math problem scrawled on a sheet of paper. Thus, neither are computers.

Now, along this continuum we can refer to the coffee cup, which is also a physical medium, does have input and output, and does allow for a change in state (let's say by the cooling of hot coffee). Does this satisfy our four phases? We can add coffee. It remains there for days more or less. We can drink coffee from it. And we might be able to use it to mix creme, so there are chemical and thermodynamic processes at work. This is input, output, processing and storage, right? Yes, however, what is missing from the system is an abstraction called information. In the physical/mental dichotomy, we generalize phenomena between those like numbers and those like molecules, and unless somehow the coffee can be made to do work on information, it is simply not a computer. Yes, but can't we measure the properties of the coffee or the cup? Yes, but again, is the system constructed and functional as an information processing cycle, and the answer is generally no. I've never heard of someone pouring a cup of coffee to do calculations, which places it in the non-computer sort of processing.

But aren't all computers physical processes too? Yes. Of course. Information does not exist without a medium. Information is part of a system generally defined with the SMCR model. For information to exist, you have to have a generator and sender of information, that information must be physically embodied in a medium, and there needs to be a receiving agent. Frequently, noise is introduced into the message through the medium, and communication processes and information theory are very interested in such processes and the mathematical truths that characterize these systems. In fact, the interconnection of information processing machines is now so common that computers and the systems for sharing information are often collectively referred to as ICT, information and communications systems.

The Human Body and Brain and Computers

Is the brain essentially a computer? The short answer is yes. John von Neumann in his classic The Computer and Brain actually does an analysis because the biological brain and the electromechanical digital computers have much in common. Now, clearly there are many differences, and von Neumann details those differences. But it is irrefutable that both ENIAC and the human CNS embody the information processing cycle. Both systems can accept a pair of numbers, recall those numbers after an elapsing of time, add those numbers, and then pass that sum outside of their respective systems. This is the foundation for the idea that computers are capable of some degree of intelligence; but mightn't one object that computers are made of inert physical matter and are programmed whereas humans are alive and have free will? That is of course a knee-jerk reaction, and doesn't hold much water upon reflection and smacks of vitalism. It was once thought that organic and inorganic chemical compounds were somehow different stuffs, but that was shown to be false. Descartes famously argued that the lack of language use meant that animals were mere automatons. (See "Quotations from Descartes on Animals as Automata" (PhilSE).) Many still believe that computers are mere bit-twiddlers whereas people understand meaning. (I push back on that in "Computers, Artificial Intelligence, and Epistemology" (PhilSE).) While the nature of AI and AGI are long, complicated subjects, the short order of it is that what separates the intelligent from the unintelligent is very much open to debate, and tests like the Turing Test or thought problems like the Chinese Room are very much philosophically difficult characterizations, both to claim and to refute with no clear consensus emerging among even the brightest thinkers.


Yes, the brain functions like a massively parallel analog computer (though neuron firing patterns are clearly both digital and analog). Yes, digital systems are essentially punctuated analog systems. Yes, 0s and 1s represented with voltages are created from square waves that could readily be sinusoidal at the whim of the architect. No, the brain does not embody an architecture remotely similar to the Harvard or Von Neumann architectures. Yes, they both use electricity, but one is clearly wetware. No, it doesn't matter what the substrate for computation is. Yes, both can clearly process numbers, language, and visual images. No, they do not do it in the same way. Yes, one is programmable to a much greater extent than the other. But that doesn't mean the other can't be given and expected to follow instructions. Yes, the human brain evolved to process information for survival value. No, current artificial computers do not have a mind in the sense that great apes do. But the continuum between worm CNSes and human CNSes is one of degree. But, to deny that human brain is a computer is be largely to affirm a lack of knowledge on what makes a system a computer to begin with.

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    Great, very detailed answer. I thought immediately of this: en.wikipedia.org/wiki/Mental_abacus An abacus is a great example of extended cognition, rather than a computer
    – CriglCragl
    Commented Feb 22, 2022 at 0:29
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    @CriglCragl I very much think it's a benefit to think of cognition as far wider than 'what goes on inside our skulls'. I think it's quite a bias of the ego to ignore all the factors that cultivate our 'personal' intelligence, everything from our community-instilled language and tools to the use of our environment. Curiously, I often visualize a calendar, boxes and all, when thinking about plans in my near future. I guess that would be a case of the mental abacus generalized. Thanks for the link!
    – J D
    Commented Feb 22, 2022 at 9:18

Each theory which proposes an answer to the question

“How does the brain operate?“

develops a theoretical model. The model tries to explain certain features of the mind.

The current model in neuroscience are neural nets. The architecture from previous computers discriminates between hardware and software with data and algorithms. Quite different neural nets: Here the data, in particular the memory, are incorporated into the weights of the neural net. And the processing of a neural net is characterized by massive parallel processings due to the many neurons of the net and the exponentially increasing number of connections.

Hence also the neural-net-model compares the mind with the operation of a computer. But the neural computer of the brain is quite different from our usual notebooks with one or a few processors which operate by sequential processing.

Added after understanding what is meant by an analog computer in the title of the original question:

I am sceptical that an analog computer may serve as model for the working of the brain: The basic constituent for the information processing in the brain is the neuron. A neuron is a binary switch, not a continuous one.

  • Actually, neurons are quite analog. Their activation thresholds are continuously varied by both excitatory and inhibitory inputs, as well as conditions (blood chemistry and other things). They fire at varying rates. This is a lot of what encodes things like light levels, sound intensity, touch pressure and so on. They are as binary as a car tire.
    – Scott Rowe
    Commented Jun 11, 2023 at 23:44

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