Bicameralism, Inner Voices, Idolatry, and Prophecy

This was a section intended for my newest book, but was cut to maintain a strict focus. If you enjoy this content, you will love “Pieces of the Puzzle“, which discusses Biblical issues such as the creation of the universe and the Exodus from Egypt from scientific and historical perspectives. You will also enjoy my paper “The Bicameral Expert“, which discusses the application of these ideas to the development of expert intuition and provides references to these ideas in the psychological literature.


In the modern world, hearing a voice inside your head is almost always taken to be a sign of mental illness, especially if it seems to be from a divine source. However, as many of us know, this was not always the case in medieval and ancient societies, which often granted special privileges or roles to people with such qualities.

Indeed, the differences between Western and world medicine when it comes to issues of mental health can be quite profound. Whereas people with mood disorders, for example, are routinely medicated and hospitalized by doctors in Europe and North America, traditional African and indigenous practitioners hold that such people are gifted in some way and require unique community supports to live comfortably and productively. Surprisingly, both approaches have successes to boast of.

Additionally, it is estimated that a significant percentage of completely normal people have an inner voice of some kind that provides ongoing guidance, critique, or narration. Even more people hear a voice occasionally, or only a couple of times in their life. Some have the harsh voice of a parent as infrequent companionship. Many don’t even realize this is unusual until they speak about it with others for the first time or enter therapy for unrelated reasons.

For the most part, these aspects of the human condition are dismissed by the mainstream as anomalies or quirks of the brain. However, in religious settings, things like voices, visions, and flashes of inspiration can be important components of personal faith practices, and have also served to catalyze entire religious movements.

What, then, are we to make of these phenomena? Are they just psychological curiosities, or is there a foundation for the belief that they constitute unique gifts? As it turns out, scientific discoveries suggest that these “inner voices” are not only natural and even useful, but may also represent the vestiges of a more ancient phenomenon tied to both religious experience and idol-worship.

Neuropsychology in a Nutshell

Put simply, neuropsychology is the study of how physical events within the brain impact the human experience. The various parts of the brain, electrical activity between neurons, and the signal patterns within brain tissue are all carefully observed by scientists and linked to phenomena that we experience in our minds.

This influential and useful field of study was largely born from clinical work with patients who had suffered brain damage. For example, the famous case of Phineas Gage, who suffered tremendous injuries to his brain and skull after an industrial accident, led scientists to discover the relationship between the frontal lobe of the brain and things like impulse control.

Over the decades, other odd cases were documented in the scientific literature, and scientists were able to piece together a general picture of how the brain works. Since the early days of neuropsychology, data from brain damage cases has been vindicated and extended using non-invasive techniques like functional magnetic resonance imaging (fMRI).

The Hemispheres of the Brain

Perhaps the most popular neuropsychological finding, however, and the one most relevant to our purposes, is the division of the human brain into a left and right hemisphere. As many of us are taught in school, the human brain can be split into two halves which collaborate to produce the mind as we know it. Generally speaking, the left hemisphere is responsible for logic, detail-oriented activity, and language, where the right hemisphere is responsible for pattern recognition, global hypothesis formation, and metaphor.

These two hemispheres are connected by the corpus callosum, a thick bundle of nerves that facilitates communication and information-sharing. Although people can live without their corpus callosum, or with a damaged one, this results in a “split-brain” syndrome where each half of the brain processes information independently, and even has a different personality to some extent.

Intuition & Inspiration

Although the many ways in which the two halves of our brain work together are still being studied by scientists, one phenomenon that has gained attention over the past couple decades is intuition. This is of particular interest in studies of expert performance, where trained professionals like athletes and radiologists can make split-second decisions with a high degree of success, often without being able to explain how they did so.

Indeed, the difference between the totality of what we know and the things we can explain is often vast, and this is especially true for experts. One of the reasons for this, it seems, is the separation between our two hemispheres and their tenuous connection through the corpus callosum. Essentially, scientists have found that our right hemisphere is responsible for recognizing patterns and generating intuitions, which are then translated into language, detailed action, and articulable thought by the left hemisphere.

When viewed from this perspective, it is probably easy to see why it is difficult for us to explain our intuitions. Essentially, the right half of our brain is busy making connections and finding patterns which are often too complex or convoluted to be condensed into linear thinking by the left half. For example, if we meet someone and have a bad “gut feeling” about them, it is likely that they displayed one or more subtle behaviors that vaguely reminded us of dislikeable or dangerous people in our past. Although we don’t always consciously consider these things, our brain does some of the work for us and simplifies all the connection-making down to a “bad feeling”. Oftentimes, we have no logical basis for this feeling, so we discount it.

A similar theme emerges in creativity studies with the phenomenon of creative insight. Much like their sense of intuition, people have limited control over their level of creativity, often relying on flashes of inspiration to help them solve difficult problems. Researchers studying highly creative individuals have found that major breakthroughs tend to occur after a long incubation period involving work on other projects, or after being exposed to a stimulus that provides unexpected inspiration. Paradoxically, it is sometimes the case that the person isn’t even working on the problem when the breakthrough occurs.

Here, the relationship between the right and left hemispheres can be observed once again. The right half of our brain is making connections, finding patterns, and developing general hypotheses about things we care about. At some point in this process – often after rest and engaging in other activities – the seed of an idea forms. This is the flash of inspiration that we are familiar with through stories like Archimedes’ bathtub discovery. However, following the initial insight, much work must be done to develop the idea to a point where it can be explained to others, even though most of the “creative work” has already been completed by that point.

As far as scientists are concerned, things like intuition and inspiration are just products of the human brain’s configuration. However, a deeper examination of these topics reveals several interesting points of consilience with phenomena described in the Jewish Bible, particularly idol-worship and the unique relationship that the Patriarchs had with God.

Julian Jaynes & Bicameralism

One of the most interesting and thought-provoking books ever written in the psychological sciences is The Origin of Consciousness in the Breakdown of the Bicameral Mind, released by Princeton psychologist Julian Jaynes in 1976. Although there are several groundbreaking ideas contained in the book, one of the most fascinating observations that Jaynes makes is that the corpus callosum is intricately linked with Wernicke’s area, the part of the left hemisphere responsible for speech comprehension and language development.

Essentially, what Jaynes found is that the signals from the right hemisphere of the brain get funneled largely into the speech-focused Wernicke’s area, and that this is why some people experience inner voices today. However, through a careful linguistic and textual review of ancient texts, Jaynes discovered that hearing voices in one’s head might have been relatively common, if not ubiquitous, thousands of years ago.

Indeed, Jaynes analyzed Homer’s Iliad and found a few notable things: first, the Greek words that are typically associated with the mind, such as psyche and nous, had different meanings at the time the Iliad was written and corresponded not to mental qualities, but to physical ones. Second, Jaynes observed that the heroes in the Iliad do not display any introspection whatsoever. Throughout the entire tale, they simply receive instructions from “the gods” and immediately act in accordance with those instructions. There are no side-stage soliloquys or internal conflicts, with all deliberation being done by “the gods”.

Jaynes concluded, perhaps controversially, that instead of “thinking” about things and coming to conclusions like we do today, ancient peoples likely had a more hemispherically-divided or “bicameral” mind, where the ability of the right brain and left brain to communicate was not yet fully developed. Instead, people’s brains came to conclusions, these conclusions ended up in Wernicke’s area, and people then heard voices in their heads that commanded certain courses of action.

The source of these voices, of course, was the person’s own intuitions and right-hemispheric conclusions. However, without an advanced understanding of psychology, ancient people were left without any clue as to where these voices came from. Jaynes hypothesizes that these voices were attributed to other people, ancestors, or “gods”, and interpreted as orders to be followed.

Bicameralism & Idolatry

Although it seems far-fetched to think of ancient peoples as being driven by voices in their heads, a great deal of enigmatic and “illogical” cultural activity can be explained through this perspective. First and foremost is the ancients’ obsession with building large and ornate statues of their deities, to which they directed veneration and worship.

Much like the Israelites’ Tabernacle was constructed to provide an earthly dwelling-place for G-d, Jaynes hypothesizes that the statues and idols erected by ancient peoples served to house or contain these “divine” voices, giving them an identifiable physical location. The worship and veneration directed at ancient statues, then, can be understood as authentic attempts to please a deity that ancient peoples genuinely believed was contained within the statue.

In some ways, this can simply be seen as a primitive attempt to make sense of a very imposing and intimidating mental phenomenon. However, not only is it objectively misguided to attribute a mental phenomenon to a gilded sculpture, from a Jewish perspective it is also an affront to and distraction from God’s sole sovereignty over the universe. Unsurprisingly, we find extensive warnings and diatribes against the practice of idolatry throughout the Jewish Bible, particularly in Isaiah 44. In short, the practice is described as exceedingly dangerous.

And [trees in the forest were] for man to ignite, and he took from them and warmed himself; he even heated [the oven] and baked bread; he even made a god and prostrated himself, he made a graven image and bowed to them. Half of it he burnt with fire, on half of it he ate meat, he roasted a roast and became sated; he even warmed himself and said, “Aha, I am warm, I see fire.”

And what is left over from it he made for a god, for his graven image; he kneels to it and prostrates himself and prays to it, and he says, “Save me, for you are my god.”

Neither do they know nor do they understand, for their eyes are bedaubed from seeing, their hearts from understanding. And he does not give it thought, and he has neither knowledge nor understanding to say, “Half of it I burnt with fire, and I even baked bread on its coals, I roasted meat and ate. And what was left over from it, shall I make for an abomination, shall I bow to rotten wood?”

From Isaiah 44

Interestingly, rabbinical commentary on idolatrous practices of ancient peoples provides us with some additional food for thought. The sages teach that the idols had an immense psychological power attached to them and that people experienced profound physical highs during idol-worship. This is perfectly in line with Jaynes’ work, which suggests that people had a very good reason to hold strong beliefs about their idols. It also supports his assertion that the mind of an ancient person was quite different from any mind alive today.

You Are What You Eat

But how does all this psychobabble relate to the Patriarchs and their connection with G-d? Well, not only would it be a relatively “simple” miracle for G-d to act as someone’s “internal voice” if He wanted to, but the importance of Torah study becomes more apparent when we consider the implications of bicameralism and intuition.

Consider the difference between an expert chess player and a novice. What, specifically, makes the expert better? First, and most obviously, the experts have played thousands of games themselves and have also reviewed hundreds or thousands of historically significant games. This gives them the ability to break the board up into patterns, or “chunks”, and have an intuition – or direct knowledge – of the best move to make. Additionally, since they have extensive practice and have seen many games, they are able to predict future events with a reasonable degree of certainty.

The same is true for how our brains work in general. Indeed, every second of every day, your brain is comparing your sensory information to as many memories as it can access, and coming to conclusions about what to do, what might happen, and what to care about. Furthermore, much like the knowledge base of an expert chess player, the things that we are intimately familiar with are easier to recall and easier to deploy in novel circumstances.

Curiously, the study of wisdom, although it is still young, is drawing some analogous conclusions. According to some researchers, one aspect of wisdom is being able to recognize patterns in the “general affairs of life” and having a sense of what actions are “best”. Although it may not yet have been stated as such, it could be said that wisdom is simply “life expertise” and its study could fall under the well-developed field of expertise research.

Given these consiliences, it seems logical to conclude that knowing as much Torah as possible would give someone an excellent foundation from which to navigate the world, as it could easily be seen as conferring a type of expertise – or wisdom. It just so happens that studying Torah is the one commandment with no minimum or maximum limit: it is said that one always benefits in this world and the next.

The Attainment of Prophecy

There is one final point of consilience to draw, and that is from one of the foremost Jewish thinkers on these matters – Maimonides. In his Guide for the Perplexed, the Rambam discusses at length the type of moral, intellectual, and spiritual preparation that is required to even be a candidate for prophecy.

“… we believe that, even if one has the capacity for prophecy, and has duly prepared himself, it may yet happen that he does not actually prophesy. It is in that case the will of God… As for the principle which I laid down, that preparation and perfection of moral and rational faculties are the sine qua non, our Sages say exactly the same: ‘The spirit of prophecy only rests upon persons who are wise, strong, and rich.’”

From Guide for the Perplexed, Maimonides

Although this may come as a surprise to non-Jewish readers, Jewish tradition holds that there have been many thousands of prophets throughout the history of Israel, all of them wise, rational, and perceptive. It is said that they all had unique and useful messages for their communities, but only the prophets whose messages had eternal significance were canonized in the Nevi’im. Clearly, this suggests that even though we probably cannot reasonably expect to prophesy in our lifetimes, the development of our rational, moral, and spiritual faculties through Torah study, Western schooling, mentorship, and life experience can elevate us into a position where we can provide visionary leadership to our communities.