Despite an interesting premise and strong introduction/background, I found the overall assertion of this book to be lacking evidence-based support. Most presented evidence is  inferred from ancient writings and archaeological findings, heavily based on subjective interpretation by Jaynes. I look forward to exploring this concept from sources that explore the neurobiological basis in a more focused and objective manner.

The first chapter gives a great refutation of many common misconceptions of consciousness, but after eliminating those, Julian Jaynes gives us his own incorrect theory of consciousness, which he dedicates the rest of the book to defending. For someone who seemed to understand how poorly defined and understood consciousness is, he failed to provide an adequate definition himself, discussing a consciousness of the concept of consciousness, or a form of self-consciousness, which he tried to assign a date to based on badly drawn assumptions from weak historical evidence. In vertebrates, there is no such thing as a bicameral mind, and there never was.

Almost anything that can be done unconsciously can also be done consciously. In fact, most of our unconscious habits initially developed through a conscious action repeated several times over. And when you're doing one thing unconsciously or semi-consciously, you're usually doing something else consciously.

The lack of expression of thoughts in writing doesn't mean they weren't thought of. Nor does the lack of understanding of free will mean that the Greeks didn't experience it. It doesn't mean that determinists don't experience it either. For something that's so difficult to put into words, one cannot expect the ancients to have a confident grasp on it. It doesn't take much to disprove this, when Eastern civilizations were more intellectually advanced at that time, and always had some element of free will in their writings. And other species without language understand the concept of choice. The writing style of any book, including the Iliad, is limited by the skill of the author. Rather than assuming that the Iliad was not consciously written, it would make more sense to argue that either Homer did not know how to write free will into characters at the time that he wrote the Iliad, it never occurred to him to do so, or he deliberately chose not to. What's obvious is he chose to write in rhythm, that's not something that could be done unconsciously. The fictional or creative works of a person cannot be used to analyze the way they think. You especially can't take Greek literature literally when it's obvious from Herodotus that they made up a whole lot of stuff for dramatic effect. It's condescending to view all ancient people as will-less and schizophrenic simply because they aren't alive to defend themselves. Schizophrenics also don't necessarily have to obey every voice in their head, and often don't. And even if these authors genuinely thought and perceived the world exactly as they wrote it, that in no way implies that the average Greek shared these same experiences. Being the author of two of the most well-known books in history, Homer was certainly unique, assuming he existed.

It makes a lot more sense to conclude that the usage of symbolism was heavy because of the limitations of language at the time to mostly concrete terminology, rather than assuming that everyone's hallucinating. Or that psychedelics had something to do with religion instead of a "bicameral mind".

Overall the main conclusion of this book is no different from the colonialist "the primitives have no mind and no feelings so you can exploit them however you want" perspective, which is also assigned to factory farm and lab animals. It's also very sexist the way it claims that women are "less lateralized" or in other words "more schizophrenic" than men.

The only part worth reading is the very beginning, which calls attention to a lot of common misconceptions in psychology and evolutionary theory that people don't normally question. The rest is stupidity. It's an embarrassment to the field of psychology that this gullible idiot who believed that every ancient myth is true became such an influential figure among pseudo-intellectuals. The lengthy title is obviously a marketing ploy to attract dumb people who want to feel smart.