my reads: ‘The Origin of Consciousness in the Breakdown of the Bicameral Mind,’ by Julian Jaynes

I had to pick up this 1976 book because it features so heavily in Robert Sawyer’s WWW series, which I wrote about recently. As Sawyer indicates, it explores an outrageous but gripping idea about how and when consciousness in humans developed (Sawyer applies some of Jaynes’ theory to his story about a consciousness awakening on the Net, and how that might happen), and it is mindblowing — pun intended.

Jaynes suggests that up until as recently as around three thousand years ago, humans were not conscious, that we lacked introspection and self-awareness. Obviously Jaynes is separating intelligence and cognition and other higher brain functions from consciousness, because it’s quite plain that prior to three thousand years ago, humans were doing things that required intelligence and cognition, like inventing civilization and fighting wars and so on. It rings weirdly true, too, because how often have you found yourself doing things that clearly require intelligence and cognition without actually being aware of having done them? Have you ever “woken up” while driving on a highway and suddenly realized that you didn’t know where the last 20 or 50 miles went? Your conscious mind was busy with other things — and I don’t mean obvious distractions such as talking on the phone, but simply wandering or daydreaming or thinking about whatever is preoccupying you at the moment — while your unconscious mind was busy with the driving.

When you consider experiences like that, it’s a little easier to understand how our consciousness is distinct from our intelligent, tool-using brains.
Jaynes goes further in exploring what that preconscious mind would have been like: the “bicameral” brain is one basically severed in two (or, more properly, one that had two halves that had not yet been connected). Instead of having two halves of the brain communicating directly with each other — that is, “conscious” thinking — these preconscious people would have “heard” “voices” from the cognitive side of their brains “telling” the other side of their brains, the one responsible for actually doing and saying things, what to do and say. Jaynes sees evidence for that in ancient literature such as the Old Testament and the Iliad: he’s suggesting that it is not metaphorical that people heard the voices of “gods” or “muses,” but that these people were literally hearing the “voices” of the other side of their brains, which they misinterpreted as coming from somewhere outside their heads.

Then, around three thousand years ago, such things as the development of writing and the growth of cities forced human minds to become more adaptable in response to changing cultural pressures, and the two distinct halves of the brain started working more in unison. (A leftover of the bicameral mind, according to Jaynes? Schizophrenia.) So the suggestion is, then, that either consciousness is cultural or that it’s biologically based and that we’re still in the process of evolving away from it.

(A pretty good fuller synopsis of Jaynes’ theory is available at Wikipedia.)

Either prospect is at once insane and compelling and hugely provocative. I was drawn to the book because I wondered whether Jaynes would address a notion that I’ve wondered about for a long time (one that I thought would be an interesting basis for a science fiction novel): What if not everyone is conscious? Jaynes does not address this, but his theory certainly supports the possibility, at least theoretically, that people could be perfectly intelligent, perfectly functional human beings without being introspective and self-aware. (And I think we all know people who appear to lack introspection and self-awareness!)

And Jaynes’ theory has implications for the future, too. If our minds — as opposed to our brains, the meat from which our minds arise — are still in the process of changing, what might our culture look like three thousand years from now? If religion is what arose from our mistaking where the voices we heard were coming from, could religion disappear as more people (perhaps) become more “conscious”? Are there fuller depths of consciousness the human mind can achieve?

This is a tough, challenging read. I sail through most books without stopping, but I found I could only take small does of Jaynes before I had to put the book down and think about what I’d already read before I could continue. And while Jaynes mounts a persuasive argument, I don’t know whether I “believe” him or not. But whether Jaynes’ hypothesis can be supported scientifically — the debate is still ongoing — it nevertheless represents a fascinating way to think about consciousness. It has certainly rocked my thinking about, you know, thinking.

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Sat, Aug 21, 2010 7:28pm

i’m still working on this book in “small doses” since you lent it to me. i can only compare it to the same experience as reading joyce’s Ulysses. the need to digest aned think about what you’d just read before being able to go on… i’m not ready to think about whether or not i buy into his theory, but it is a good workout for my conscious brain…

Sat, Aug 21, 2010 7:37pm

First came across this in a panel footnote to a Micronauts comic back in the early eighties.I’m (hopefully) wiser now but still makes for heavy reading.

Sat, Aug 21, 2010 7:59pm

I’m about a third of the way through Sawyer’s “Watch” on your recommendation, and I’m greatly enjoying it. I’ve heard of Jaynes’ theory and I’m interested in checking out this book as well, although his methodology as you describe it–using ancient literature to try to prove a scientific point–reminds me of Immanuel Velikovsky, who tried to use ancient legends to prove the historical occurrence of highly improbable (to say the least) astronomical events, and whose theories were debunked by Carl Sagan among many others. Like you, I’d be interested in seeing if Jaynes’ hypothesis stands up to real scientific scrutiny. It certainly is a provocative idea.

Sat, Aug 21, 2010 8:43pm

I am so happy that you found this book. It is a long time favorite of mine. Not because I “believe” his theory but rather because I am endlessly impressed by the methodical and rational approach that he takes to examining his theory. An absolute model of what a serious scientific discussion is supposed to look like.
Over the years I have found him an impressive first look at a variety of far flung fields i.e. hypnotism and The Ilead.
A great read.

Sat, Aug 21, 2010 10:22pm

reminds me of Immanuel Velikovsky, who tried to use ancient legends to prove the historical occurrence of highly improbable (to say the least) astronomical events,

To be fair to Jaynes, he doesn’t use *only* ancient literature to support his theory…

Sun, Aug 22, 2010 12:28am

Never heard of Jaynes. After reading the wikipedia link, I have to say his theory sets off my pseudoscience warning system like an air raid siren.

From the summary it seems he draws heavily from ancient literature that western audiences would be quite familiar with, such as Greek mythology and the Old Testament, which would seem to support his 3000 years estimate. I wonder what he makes of Muhammad or L. Ron Hubbard. Does he take examples from Hindu, or Chinese, or Native American traditions?

Sun, Aug 22, 2010 1:47am

I remember reading about this a while back. I think Alan Moore cited it in something back in the day. (It partly appears in Neal Stephenson’s Snowcrash to some extent, particularly the notion that consciousness is a fairly recent ‘invention’ of the Sumerians)
I can’t remember too much about the details, but the indexed version is that Jaynes’ theory is at best out of date compared to contemporary knowledge in neuroplasticity and paleoanthtopology.

He kind of relies too heavily on left brain/right brain stuff which was very big at the time, but has gone in and out of fashion over the years. Again, I’m no expert on this in the slightest but it’s my vague recollection that while brain halves are important there’s exponentially more oddness afoot in our scones.
For instance, a necessary procedure in severe juvenile epilepsy is a hemispherectomy. Which is exactly what it sounds like; half the kid’s brain is cut out. People who have undergone this procedure develop quite normally in most cases as far as anyone can tell, lesser motor control on one side being the most notable thing.

But I’d have to go see if I remember this correctly.

Sun, Aug 22, 2010 1:50am


Actually, the book is an excellent example of scientific thinking and process. Jaynes states a problem (it is unclear when humans first became conscious), rigorously defines his terms, establishes a hypothesis and compares it to known data. He defends the hypothesis, but also describes outliers and non-matching information (the wikipedia article mentions Gilgamesh) and proposes a reasonable cause to exclude that data. Finally, he describes methods that can be used by current scientists to test the hypothesis in a rigorous manner. I’m not sure what steps of the scientific method he may be missing.

Pseudoscience doesn’t mean an incorrect hypothesis, it just means someone skipped a step or two in the process, usually to ignore outlying information or to provide methodology for other parties to test the hypothesis rigorously.

Les Carr
Les Carr
Sun, Aug 22, 2010 4:05am

How wonderful to find a FF discussion on this book. I too remember the thrill and consternation of grappling with its ideas after a colleague had recommended it to me. Although it’s out of my area of specialism (I’m an information scientist and he was a professor of cognitive science) this whole area of explaining the conscious experience (with its zombies and zimboes and Chinese rooms and real life examples of brain ‘plumbing’) is fascinating. The last great problem of science, some would say.

Writing this comment makes me wonder when the last time was that I had such an experience – being simultaneously thrilled and shocked by the ideas in a piece of literature (book / film / TV). And is truth always more shocking than fiction?

Patrick Brown
Sun, Aug 22, 2010 4:20am

There’s a related theory that I think I read in Stephen Pinker’s “How the Mind Works”, which is that the mind, in humans and other animals, is modular – it has discrete processes that each evolved to do one particular thing. The difference between humans and other animals is that humans can use modules for things they didn’t evolve to do, by analogy, while other animals can’t.

For example, chimps have a mental process to rank other chimps by status in the group, but can’t apply that process to rank the relative status of other animals, or to rank inanimate objects by size – but humans can and do use the same process to rank all sorts of things by all sorts of criteria. Analogy allows us to break down the walls between these separate processes and have a more unified mind.

(Just a vaguely interested amateur, and can’t lay my hands on the book, so no guarantees for the accuracy of my memory or understanding of the theory)

Sun, Aug 22, 2010 5:00am

The driving “waking up” seems to be pretty well explained by a lack of short-term to long-term memory transfer; there just wasn’t anything memorable happening, so you don’t remember it.

I tend to regard Jaynes in much the same light as Jared Diamond: he becomes so enamoured of his theory that he gets very selective about the data, in order to make the idea look better-supported than it is.

Sun, Aug 22, 2010 10:04am

A big difference between Velikovsky and Jaynes is that Velikovsky was using ancient legends to describe the history of our solar system while Jaynes is using ancient literature to look at the pyschology of ancient people; I think Jaynes’ use is far more appropreiate. Don’t we often use the literature of a time period to understand the psychology of that time? A few months ago I was reading an academic book about how Victorian literature reflected changing ideas about love and morality in a transistion from a land-based society to a capitalist society.

Jaynes is more ambitious, perhaps over reaching, perhaps wrong, but not out of line in proposing and trying to prove his idea. I do like the idea that hearing voices and listening to gods are essentially the same thing biologically, and that both hallucinations caused by one part of the brain talking to another. I suspect that this began long before literature was being written down, and wonder if the diminishment of gods in literature is because people are becoming better and better at telling the difference between talking to themselves and talking to gods. The biggest mistake I think people are likely to make is to assume that consciousness is a sudden thing, while evolution is a gradual thing. If evolution is gradual, then in theory humans are always evolving, so why shouldn’t it show up in the literary record as well as the fossil record?

Unfortunately, it also seems to me to be an unproveable pet theory, lacking time travel to go back and test it.

Sun, Aug 22, 2010 11:21am

The biggest mistake I think people are likely to make is to assume that consciousness is a sudden thing, while evolution is a gradual thing.

One of the shocking/thrilling ideas (hi, Les!) in the book is, to me, is the notion that perhaps the development of consciousness is NOT suddenly: that is, that it is not complete in the world around us today.

I wonder what he makes of Muhammad or L. Ron Hubbard. Does he take examples from Hindu, or Chinese, or Native American traditions?

Not that I recall, though of course he was writing for a Western audience and needed examples his readers would be familiar with. Applying his methods to non-Western (written, not oral) literature would be an execellent way of testing his hypothesis.

The driving “waking up” seems to be pretty well explained by a lack of short-term to long-term memory transfer; there just wasn’t anything memorable happening, so you don’t remember it.

Perhaps a better example is this: Have you ever gotten in your car with the conscious intent to drive somewhere in particular, and then found that you automatically started driving somewhere else, in the direction of somewhere more a habit for you to drive?

(The driving examples are mine, by the way, not Jaynes!)

Sun, Aug 22, 2010 2:31pm

I dunno… It’s interesting as a hypothesis… But is there any biological evidence that the corpus callosum was non-existent or less developed in the past? From what I gathered, you can find genetically modern humans (as in essentially indistinguishable) at least 100,000 years ago. It certainly seems like any such change would have had to occur prior to the spread of humans out of Africa ~70,000 years ago. Otherwise, how could the sudden appearance of consciousness have spread throughout the global population, even assuming it was supremely advantageous (which seems like a big leap if we’re already assuming humans could have all the trappings of tool use and civilization without it).

And there are people who lack a corpus callosum, either from having it cut or as the result of a developmental disorder. The result isn’t a lack of consciousness. The result is that they still have a sense of “self”, but have a variety of other, specific, problems. Like, not being able to tell if someone is angry because the parts of the brain that process the image and see a face, and the part that references that face against possible expressions and comes up with “angry”, are on different halves of the brain. Or limb coordination problems, like when they try to perform a task with one hand whose controlling hemisphere is better suited to it, the other hand will try to take over, sometimes forcing them to sit on the hand just to keep it out of the way.

So they can live mostly normal lives, they still are self-aware people as you’d recognize them, but they do have some significant practical issues.

If we assume these issues were not present in the pre-conscious human (and well let’s just say hunting is a problem if you can’t make your hands work together), then this would mean there was a massive amount of re-wiring of the brain that could only occur after the end of the bicameral mind. I just don’t see how that kind of genetic drift could have occurred to the entire global population in the last three thousand years.

Plus, looking at the brains of other animals, they have fully developed corpus collosums. Their brain hemispheres communicate readily and frequently. The biggest difference between ours and theirs is the size of our cerebrum. That size was reach a long time ago, but it certainly could have changed its organization since. I think that, not the bicameral mind, is a more productive line of inquiry to finding the roots of human consciousness.

I see other problems, with the social aspects. I mean I get how you can do a large number of things without being conscious of it. But I don’t really see how you can have things like art, or religion, without self-awareness. What do the concepts of “sin”, “forgiveness”, and “after-life” even mean without a conscious understanding of ones own ability to choose, and of one’s own mortality. There are animals other than humans that have self-awareness but not art or religion (some do have art after a fashion). I think those are the more advanced concepts, and consciousness is the pre-requisite.

But really, that doesn’t matter nearly as much to me as the biological issues. If he said 100,000 years ago, I’d find that plausible. 3,000 years ago? 3,000 years ago there were civilizations in the Americas, and on Pacific islands with little to no contact with the rest of the world. I see no way that much population-wide genetic drift could occur. I don’t know if he addresses this issue or not, but it must be addressed before I could take the premise seriously.

Sun, Aug 22, 2010 2:46pm

Oh, and if you want a non-metaphorical explanation for why people heard the voices of gods, muses, and spirits, or seeing them… They’re called hallucinogens, and mankind has been using them for a very long time. Especially priests, shamans, and oracles, as official parts of their ceremonies. Different hallucinogens produce different hallucinations, some mostly auditory, some mostly visual, some both, some with weird synethesia (e.g. seeing sounds, smelling colors) effects.

And when combined with visible physical problems, like rashes or convulsions, hallucinogens could have lead to a belief in witches.

Sun, Aug 22, 2010 2:59pm

(And I think we all know people who appear to lack introspection and self-awareness!)

Er, I don’t. I know people who appear not to exercise it. I know people who appear to want to avoid it at all costs. I don’t know anyone who appears to be incapable of it. Many times the poster-children for lack of introspection, at a point where this has cost them greatly, cost them everything, suddenly find themselves looking at their lives and seeing what is wrong with it.

I don’t believe they suddenly gained the ability. I think they simply had not chosen to use it.

Sun, Aug 22, 2010 6:09pm

Way to go, you guys found Pinker too!
Just a couple of comments. Jaynes isn’t a simple theory. It isn’t psudoscience. He doesn’t try to prove his ideas by reference to myths. He does however examine the myths to see if they disprove his theory. This makes perfect sense. If, for example, the obviously self aware hero of the Odyssey predates the fully Gods driven characters of the Ilead then his theory must be adjusted to fit the facts.
The problem is that hardly any of the posters have read the book so they are, perforce, discussing at third hand. For example, my recollection of Mary Anns example of the car driver is that it was used by Jaynes as an illustration of what it might have felt like to live in the preconscious state. Not as a proof of the states existence.
Similarly, CBs questions about evolutionary change in the brain is, as I recall, addressed by Jayne as reflecting the possibility that, while the brain had changed, the culture had not, and that the people more isolated areas like the Americas, were still living in a top down preconsious society.

In any event, whether true or not, the book itself leads to other works, like Pinker, and as MA has pointed out makes for deep thinking.

Sun, Aug 22, 2010 7:47pm

My synopsis of Jaynes’ theory is extremely simplistic, and he does deal with many of the objections raised here in interesting ways.

And there are people who lack a corpus callosum, either from having it cut or as the result of a developmental disorder. The result isn’t a lack of consciousness.

Right. Which suggests that (if you’re going to consider Jaynes’ theory) consciousness could be *cultural.* Or at least as cultural as it is biological.

I know people who appear to want to avoid it at all costs. I don’t know anyone who appears to be incapable of it.

I don’t know: Do we? Could it be possible that those who lack conscious are unwittingly aping it?

None of this is Jaynes, of course. But the idea that some of us could lack consciousness is one that fascinates me: it’s not something I necessarily believe, but it is something I find interesting as a thought experiment. I mean, much of how our cultural operates on an interperson level comes about because we assume that everyone is as conscious as we are. How much might our assumptions contribute to attributing consciousness if it weren’t there?

Like I said, it’s something interesting to think about.

Sun, Aug 22, 2010 10:05pm

I mean, much of how our cultural operates on an interperson level comes about because we assume that everyone is as conscious as we are. How much might our assumptions contribute to attributing consciousness if it weren’t there?

It would definitely make a good premise for some interesting speculative fiction.

If we believe some of us are more highly evolved, would we use it to justify preferential treatment for the “conscious” and perhaps atrocities against the “preconscious”? (I suppose I’m thinking about this because I recently read John Wyndham’s The Chrysalids, which resolves its “‘old’ humans versus ‘new’ humans” conflict in ways I don’t like…)

Would “preconscious” be the new accusation to hurl against political or ideological opponents? Would it undermine efforts at diplomacy? (“There’s no use trying to reason with my religious parents/evangelicals/the North Koreans; they’re preconscious!”)

Would we devise a test to determine who’s “conscious” and who isn’t? Would it be any more effective than Baltar’s Cylon test? Would Internet trolls fail the test? ;-)

Mon, Aug 23, 2010 1:48am

ObPeeve: there is no such thing as “more highly evolved”. All you can rate on an evolutionary scale is “more specifically adapted to its habitat” – and that’s not always a good thing, for example when the habitat changes.

Victor Plenty
Victor Plenty
Mon, Aug 23, 2010 6:39am

RogerBW, while it’s true that current evolutionary theory hates to talk about evolution in terms of “more” or “less” evolved, it seems to me there is some basis for calling some species “more highly evolved” than others, and it’s the exact opposite of the specialized adaptations you mention.

Tremendous reproductive advantages have been gained by a few species that became extreme generalists, and learned to adapt rapidly to new environments or changed environments. It seems reasonable to me that we could describe these highly adaptable species as more highly evolved, compared to those that would quickly die out if some small detail of their habitat changes.

Of course the single large mammal known to thrive in the widest range of habitats is the human species, and it’s dangerous to assume our variant of this adaptability will prove to be an evolutionary advantage in the long run, until we learn whether we will be able to control our urge to use up all available resources we can lay our grubby mitts on.

But if we succeed in doing that, and in becoming a spacefaring species, that will be a level of reproductive success truly and completely unprecedented in the known history of terrestrial life, and we’ll finally earn the title of “more highly evolved” that we’ve been arrogantly assuming for ourselves since the days of Darwin.

Mon, Aug 23, 2010 8:39am

there is no such thing as “more highly evolved”.

RogerBW: My statement was “If we believe some of us are more highly evolved,” and I was speculating on what the social implications of believing such a thing might be.

Mon, Aug 23, 2010 8:41am

I have to admit I read the book seven years ago, so what I remember is pretty selective, the stuff that helped me understand my worldview rather than Jaynes’. Would you believe I remember it was seven years ago because I remember which bar I got into an argument about it in?

It is my impression that consciousness is the brain watching its own actions, and that it is the most recent addition to brain function. If we are still learning to be conscious, it makes sense that the struggle to be more and more conscious would show up in the literary record. Changes in human love, compassion, honor, and spirituality have.

Mon, Aug 23, 2010 5:56pm


I tend to agree with you that hallucinogens are the far less complex theory (and in the case of things like peyote have a documented side effect of the feeling of spiritual contact), but it is worth noting that Jaynes doesn’t really posit a physiological change, more of a change in the way different portions of the brain communicate. And damage to or abnormalities of the corpus callosum has been positively correlated with schizophrenia for some time, so an interruption in the appropriate location could interfere with this communication.

Jaynes puts forth the hypothesis that the brain had to learn to access the higher order conscious thoughts to survive in new and complicated situations. To use a horrible analogy, the evolution was in the software rather than the hardware. Which is what he means by a cultural evolution; the change was a learned behavior. It’s also consistent with modern belief on child development. Certainly no one associates very young children with what Jayne defines as consciousness. The behavior of introspection and meta-thinking is a later stage development, and if Jayne is right it’s a stage that wasn’t always present.