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Is Consciousness a Recent Development?

Photo: Homer, British Museum, Public domain, via Wikimedia Commons.

Nautilus recently republished science writer Veronique Greenwood’s thoughtful 2015 essay on the work of consciousness researcher Julian Jaynes (1920–1997). His was surely the most eclectic theory to command a broad public following decades ago — and worth another look for that reason.

Drawn from an early age to the study of consciousness, Jaynes lived in and around Princeton University and theaters. It wasn’t until 1976 that he published The Origin of Consciousness in the Breakdown of the Bicameral Mind (Houghton Mifflin, 1976).
He had decided, after much research, that that before 3,000 years ago, people were not really conscious They were

… instead relying on a two-part, or bicameral, mind, with one half speaking to the other in the voice of the gods with guidance whenever a difficult situation presented itself. The bicameral mind eventually collapsed as human societies became more complex, and our forebears awoke with modern self-awareness, complete with an internal narrative, which Jaynes believes has its roots in language.


For example, Jaynes denied that the characters in Homer’s Iliad (9th century BC) were conscious. When they had insights, they imagined the gods speaking to them. In reality, on his view, the right hemisphere of the brain was speaking to the left hemisphere. Later, according to his theory, language development enabled our bicameral (two-chambered) human brains to become integrated and that’s how modern consciousness developed.

The book was reviewed in top venues, became a best-seller, and has been reprinted regularly ever since. There is a small but active Julian Jaynes Society today.

Jaynes Could Not Find an Evolutionary Origin of Consciousness

Part of the attraction of Jaynes’s only book may have been that it was a break from physicalism and behaviorism, written in a poetic style. Greenwood recounts, for example, his efforts in the late 1940s to research consciousness via animal studies:

For a while, he believed that if a creature could learn from experience, it was having an experience, implying consciousness. He herded single paramecia through a maze carved in wax on Bakelite, shocking them if they turned the wrong way. “I moved on to species with synaptic nervous systems, flatworms, earthworms, fish, and reptiles, which could indeed learn, all on the naive assumption that I was chronicling the grand evolution of consciousness,” he recounts in his book. “Ridiculous! It was, I fear, several years before I realized that this assumption makes no sense at all.” Many creatures could be trained, but what they did was not introspection. And that was what tormented Jaynes…

He later wrote that a psychology based on rats in mazes rather than the human mind was “bad poetry disguised as science.”


By 1969, he had begun to think of consciousness as originating in cultural change rather than evolution so he envisioned a sharp break within known human history in which modern consciousness was born:

So he decides to read early texts, including The Iliad and The Odyssey, to look for signs of people who aren’t capable of introspection — people who are all sea, no rime. And he believes he sees that in The Iliad. He writes that the characters in The Iliad do not look inward, and they take no independent initiative. They only do what is suggested by the gods. When something needs to happen, a god appears and speaks. Without these voices, the heroes would stand frozen on the beaches of Troy, like puppets.


In this telling, overpopulation, natural disasters, and wars broke down the bicameral mind, allowing the modern conscious mind to slowly emerge, “one better suited to the chaos that ensued when the gods went silent,” as Greenwood puts it.

What Made the Bicameral Mind So Popular?

I remember reading Homer’s Iliad in the original Greek at university about five years before Jaynes’s book was published. Neither the lecturer nor the students had any sense that the characters in the story were not conscious. Thus, when I read Jaynes’s book in the early Nineties, I dismissed the theory outright. But most readers in those days had not read the Iliad, though they probably knew of it by name.

The idea of originally unconscious people — made conscious by a crisis that marked the death of the gods — was a wonderful historical myth for the times. It had all the cultural reassurance of materialism but it retained a sense of mystery and fired the imagination. Greenwood writes,

It’s a sweeping and profoundly odd book. But The Origin of Consciousness in the Breakdown of the Bicameral Mind was enormously appealing. Part of it might have been that many readers had never thought about just what consciousness was before. Perhaps this was the first time many people reached out, touched their certainty of self, and found it was not what they expected. Jaynes’ book did strike in a particular era when such jolts were perhaps uniquely potent. In the 1970s, many people were growing interested in questions of consciousness.


Few stopped to ask how a poet like Homer wrote the Iliad if he really was not conscious himself (?) or how language can give rise to consciousness, as opposed to the reverse.

The fifty years since Jaynes’s bicameral mind seized the public imagination have seen the bloom of eliminative materialism (consciousness is an illusion) and panpsychism (all life forms are conscious). And neither has answered any big questions; human consciousness is as great a mystery as ever.

But Jaynes got one thing right. The human mind has no history. There is no reasonable account of its origin in the grunts and snarls of animal life. His effort to pinpoint its sudden emergence in historical time implicitly underscores that fact, even if his chronology is surely wrong. He certainly owes Homer an apology.