[The dissertation below defends the philosophical-psychological hypothesis of the evolution, in the last six thousand years, of the human mind, from a Bicameral to a Unicameral consciousness, through the structuring of society, and its existence in the early periods of human history]

[This is a discussion focused solely and exclusively on the human mind, regardless of the psyche of the rest of the animal kingdom]

[The following analysis and its conclusions may be of difficult understanding for certain readers without an average knowledge of history, psychology, and philosophy, therefore, it is necessary that the reading be carried out with patience and diligence so that it is easily digested]

First Topic: The Search for the Human Consciousness

The discussion of what substantiates the human mind and its consciousness, is a question that has been sought for the answer for more than 2,000 years, having been addressed even by the classical Greeks, such as Isocrates - 436 BC to 338 BC - who saw the spirit - pneuma - as if existing in humanity, through the internal and external rhetorical expression of feelings, logic and imagination - therefore, rhetoric would be the substance of the human intellect - or as Plato would establish, that "the intellect of Man is an infinite extension between the ideal metaphysical and the physical material worlds, who would be aware of himself and his finitude as well as of his absolute existence in the world of ideas".

The perception of conscience as something immaterial and essentially transcendental would remain the norm for more than 1600 years, until, with the intellectual revolutions of the centuries permeated by the Enlightenment, a new path that could answer the question of conscience had been discovered, which is made concrete for its foundation in research and historical-rational evidentiality.

In fact, Western philosophers since the time of Descartes and Locke have struggled to comprehend the nature of consciousness and how it fits into a larger picture of the world. One of the primary conceptions of the perception of "the body's interdependent existence with the mind" had been established by the dualistic view.

The dualistic perception of the relationship between the body and the mind was first established by Descartes - 1596 AD to 1650 AD - with his "Cartesian Dualism" in which he argued that "the mind is a nonphysical — and therefore, non-spatial — substance".

It is interesting to realize that, every inquiry about the human mind until Descartes, was conceived as completely metaphysical, without any connection or interaction with the physical - brain - body. It is with Descartes that, for the first time in history, through rational intuition, we have the hypothesis of the intrinsic interaction of a part of the body - in his - Descartes's - case, the pineal gland - for the expression and projection of consciousness.

As Gert-Jan Lokhorst, in his article, "Descartes and the Pineal Gland" states:

"He was the first to suggest that the interaction between these two domains - mind and body - occurs inside the brain, he hypothesized that perhaps this occured in a small midline structure called the pineal gland. Refuted or not, the fact is that it was with his intuition that the contemporary quest for consciousness began."

With the rational view established, several other thinkers, psychologists and philosophers put themselves at the forefront of the duty to seek the answer to consciousness, and several decided to seek this conclusion in history; more precisely, in ancient human history.

Second Topic: The Historical-Evolutionary View

Entering the 20th century, already having the historical and archaeological record of the distant past, commonly known as the "Bronze Age", and its societies, many sought to study through history, how consciousness could have arisen in humanity. One of the pioneers in this field was Julian Jaynes - 1920 to 1997 - who spent 25 years of his academic career studying the development of human consciousness, which, within the archaeological and historical records of the ancient period, seemed to resemble another type of aspect of "consciousness" other than the one pre-established by the evolutionary vision of its time - which categorized "conciousness" as simply "awareness" -.

As Jaynes would state in his book, "The Origin of Consciousness in the Breakdown of the Bicameral Mind":

"This search took me to the earliest writings of mankind to see if we can find any hints as to when this important invention of "consciousness" might have occurred. I went to ancient texts searching for early evidence of consciousness, and found what I believed to be evidence of remarkably recent voice-hearing without consciousness."

In his studies of the classic epic of the "Iliad", when assessing the linguistics of the individual perceptions of its characters and their allegories regarding the introspective nature of the existence of the Archaic Greeks, Jaynes would state:

"In the semi-historical Greek epic "The Iliad", the earliest writing of men in a language that we can really comprehend, when looked at objectively, reveals a very different mentality from our own.”

Through the following conclusion, Jaynes set out to describe the theory of how consciousness was born out of the end of the Bicameral mind:

- Humanity, until the period of the first historical manuscripts, does not present in any form a conception of the understanding of conscience - introspectiveness, which has the capacity to "think about itself -;
- We cannot access and study the habits and psychological functionalities of the ancients in first instance - from 700 BC to 6000 BC - to prove through evidence that they had the mental and conceptual structure that humans post-500 BC, however, there is historical-archeological evidence that strengthens the contrary notion;
- Therefore, the ancient human conscience was not necessarily identical to the current one.

The Bicameral theory of mind would therefore be established.

Third Topic: The Origin of Consciousness in the Breakdown of the Bicameral Mind

In his theory, Jaynes goes on to explain consciousness, “the human ability to introspect”. Abandoning the assumption that consciousness is innate, Jaynes explains it instead as a learned behavior that “arises from language, and specifically from metaphor”.

With this understanding, Jaynes then demonstrated that ancient texts and archeology can reveal a history of human mentality alongside the histories of other cultural products. His analysis of the evidence led him not only to place the origin of consciousness during the 2nd millennium BC but also to hypothesize the existence of an older non-conscious mentality that he called the "bicameral mind", referring to the brain’s two hemispheres.

In the third chapter of the book, "The Mind of the Iliad", Jaynes states that people of the era - Bronze Age - Ancient Era - - had no consciousness:

"There is in general no consciousness in the Iliad. I am saying "in general" because I shall mention some exceptions later. And in general therefore, no words for consciousness or mental acts. The words in the Iliad that in a later age come to mean mental things have different meanings, all of them more concrete. The word psyche, which later means soul or conscious mind, is in most instances life-substances, such as blood or breath: a dying warrior bleeds out his psyche onto the ground or breathes it out in his last gasp. The thumos, which later comes to mean something like emotional soul, is simply motion or agitation. When a man stops moving, the thumos leaves his limbs. But it is also somehow like an organ itself, for when Glaucus prays to Apollo to alleviate his pain and to give him strength to help his friend Sarpedon, Apollo hears his prayer and “casts strength in his thumos”. The thumos can tell a man to eat, drink, or fight."

"Bicameral" mentality would be non-conscious in its inability to reason and articulate about mental contents through "meta-reflection", reacting without explicitly realizing and without the meta-reflective ability to give an account of why one did so.

The bicameral mind would thus lack metaconsciousness, autobiographical memory, and the capacity for executive "ego functions" such as deliberate mind-wandering and conscious introspection of mental content. When bicamerality as a method of social control was no longer adaptive in complex civilizations - as in the Bronze Age Collapse -, this mental model was replaced by the conscious mode of thought which, Jaynes argued, is grounded in the acquisition of metaphorical language learned by exposure to narrative practice.

Ancient people in the bicameral state of mind would have experienced the world in a manner that has some similarities to that of a person with schizophrenia. Rather than making conscious evaluations in novel or unexpected situations, the person would hallucinate a voice or "god" giving admonitory advice or commands and obey without question.

The perception is that, humanity, until that point, without the scientific, social-political, moral and ethic perception of reality, would see their own "counsciouness" - the voice, aka, the introspectiveness of the subjective - as being the hallucinating voice of the Gods, as until then, mythology was seen as the principle that made reality "real".

The bicameral individual was guided by mental commands believed to be issued by external "gods" who told commands which were recorded in ancient myths, legends and historical accounts.

As Jaynes affirms:

"In ancient times, gods were generally much more numerous and much more anthropomorphic than in modern times, this was because each bicameral person had their own "god" who reflected their own desires and experiences."

Such a mentality is not seen in today's humanity, and the cause can also be found in the study of history.

Fourth Topic: Breakdown of Bicameralism

Jaynes theorized that a shift from bicameralism marked the beginning of introspection and consciousness as we know it today. This bicameral mentality began malfunctioning or "breaking down" during the 2nd millennium BC. He speculates that primitive ancient societies tended to collapse periodically, for example, Egypt's "Intermediate Periods", as well as the periodically vanishing cities of the Mayas, as changes in the environment strained the socio-cultural equilibria sustained by this bicameral mindset.

The Bronze age collapse of the 2nd millennium BC led to mass migrations and created a rash of unexpected situations and stresses which required ancient minds to become more flexible and creative. "Self-awareness", or "consciousness", was the culturally evolved solution to this problem.

This necessity of communicating commonly observed phenomena among individuals who shared no common language or cultural upbringing encouraged those communities to become self-aware to survive in a new environment. Thus consciousness, like bicamerality, emerged as a neurological adaptation to social complexity in a changing world.

In Jaynes words:

"When the world ended, and when the Gods stopped talking to us, in a sense, we made ourselves our own Gods."

Fifth Topic: The Evidence in the Dawn of Society

Having clarified all the points necessary to understand my arguments and my statements, it remains to present the evidence to you.

In addition to the evidence Jaynes demonstrates in his book, using the periods from 2000 BC to 700 BC, I believe that a greater and more substantial evidence about the bicamerality of the mind can be found, however, in a much older period; at the birth of society, more precisely, at the foundation of its first "city" - Uruk.

The Uruk period - 4000 to 3100 BC - existed from the protohistoric "Chalcolithic" to the "Early Bronze Age" period in the history of Mesopotamia, after the "Ubaid" period and before the "Jemdet Nasr" period. Named after the Sumerian city of Uruk, this period saw the emergence of urban life in Mesopotamia and the Sumerian civilization.

On the cusp of prehistory and history, the Uruk period can be considered "revolutionary" and foundational in many ways. Many of the innovations which it produced were turning points in the history of Mesopotamia and indeed of the world.

It is in this period that one sees the general appearance of the potter's wheel, writing, the city, and the state. There is new progress in the development of state-societies, such that specialists see fit to label them as "complex" - in comparison with earlier societies which are said to be "simple" -.

This period is, therefore, as a crucial step in the evolution of society, a long and cumulative process whose roots could be seen at the beginning of the Neolithic more than 6000 years earlier and which had picked up steam in the preceding Ubaid period in Mesopotamia.

The 4th millennium saw the appearance of new tools which had a substantial impact on the societies that used them, especially in the economic sphere.

Some of them, although known in the preceding period, only came into use on a large scale at this time. The use of these inventions produced economic and social changes in combination with the emergence of political structures and administrative states.

In the agricultural sphere, several important innovations were made between the end of the Ubaid period and the Uruk period, which have been referred to in total as the "Second Agricultural Revolution" - the first being the Neolithic Revolution -. A first group of developments took place in the field of cereal cultivation, followed by the invention of the ard - a wooden plough pulled by an animal - towards the end of the 4th millennium BC, which enabled the production of long furrows in the earth. This made the agricultural work in the sowing season much simpler than previously, when this work had to be done by hand with tools like the hoe.

The development of woolworking, which increasingly replaced linen in the production of textiles, had important economic implications. Beyond the expansion of sheep farming, these were notably in the institutional framework, which led to changes in agricultural practice with the introduction of pasturage for these animals in the fields, as convertible husbandry, and in the hilly and mountainous zones around Mesopotamia - following a kind of transhumance -.

In architecture, the developments of the Uruk period were also considerable. The builders perfected the use of molded mud-brick as a building material and the use of more solid terracotta bricks became widespread. They also began to waterproof the bricks with bitumen and to use gypsum as mortar.

New types of decoration came into use, like the use of painted pottery cones to make mosaics, which are characteristic of the Eanna in Uruk, semi-engaged columns, and fastening studs.

The Uruk period provides the earliest signs of the existence of states in the Near East. What kind of political organisation existed in the Uruk period is debated. No evidence supports the idea that this period saw the development of a kind of "proto-empire" centred on Uruk, as has been proposed by some historians. It is probably best to understand an organisation in "city-states" like those that existed in the 3rd millennium BC.

It is clear that there were major changes in the political organisation of society in this period.

It is visible the complexity already pre-established by humanity in its most primitive periods, which comprised several aspects of what is now also understood as "society".

However, even though a civilization has been developed that borders on the administrative and bureaucratic complexity of contemporary society, with its intrinsic needs for economic, theological, historical and administrative records, at no time, tablet, inscription, tomb, memorial, etc... is described in any way, the individual introspective perception of the self-conscious mind. However, we have thousands and thousands of references to "divine prophecies", "sacred commands", "words of Gods", which are projected to the smallest detail.

In Conclusion:

In a comparative analysis of both evidential historical contexts - the lack of evidence to the perception of individual conscience and the large amount of evidence of the lack of individual conscience on ancient times - together with the analysis of the societal archeological context of the time, the following statement can be made:

"Humanity, in a hypothetical scenario where its mind would be structured bicamerally, would still be able to develop a society as complex and bureaucratic as that structured by unicameral humanity."

Therefore, the following affirmation is correct:

"For the historical evidence of the lack of citations on the subjectivity of the introspectivity of human consciousness, and for the vast amount of evidence that supports the hypothesis of an ancient bicameral humanity, the most substantial scenario in history is that of the Bicamerality of the Mind."

And therefore, the first civilization - Sumer - had been developed and composed by bicameral individuals.