Evolution of Human Consciousness

* Book: Merlin Donald. A Mind So Rare: The Evolution of Human Consciousness. Norton, 2001

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Summary

By Trevor Stone:

"In the ten years after Origins of the Modern Mind was published, the cognitive science field changed significantly. Authors released a host of books with popular audiences in mind. The laboratory was supplemented with, and in some cases largely replaced by, a heavy dose of the armchair. The evolutionary psychology camp are among the most vocal of these authors, and may be the most influential among casual readers. These fundamentalist neo-Darwinists attempt to explain all aspects of the human mind by appeal to the principles of natural selection. In the process, most of them downplay or try to eliminate consciousness in the picture of cognition.

Donald begins AMSR by distancing his view of consciousness from that of what he calls "the Hardliners:" camp of neo-Darwinists and other reductionists, such as postmodernists. His project is to give a positive account of consciousness and how it came about. Unfortunately, Donald doesn't argue against any specific Hardliner arguments, nor does he credibly present the Hardliner views of his theory's key elements. The reader is thus left without a good understanding of why people hold Hardliner views. While this is philosophically somewhat disappointing, Donald's goal isn't so much to refute the Hardliners as it is to present his own theory on its own merits. His occasional jabs at Hardliners are meant to provide some context rather than to present a complete picture of existing work.

Although he doesn't respond to many specific arguments, Donald does battle with some commonly held beliefs, most remarkably by arguing in favor of a homunculus. He thinks that the "homunculus is heresy" idea is something of a knee-jerk reaction, and points out that Hardliners replace a single man-in-the-head with a cadre of men-in-the-head, even more impenetrable than the original, without explaining perceptual unity. In Origins, he says the homunculus "cannot be explained away as an epiphenomenon, "reduced" to algorithms or neural nets, or simply denied existence." (p. 365) The homunculus is what is to be explained, and in AMSR he aims to do so without invoking the spectre of Dualism.

After revealing his biases, Donald sets out to give an account of human consciousness while acknowledging that a complete account is many years away. His goal is to describe consciousness at the functional level, rather than providing an evolutionary account or a full description of how neurological activity produces consciousness. However, as a neuroscientist, he builds this functional model upon facts about the brain. He aims for an inclusive view of consciousness, "a multilayered, multifocal capacity and a deep, enduring cognitive system with roots far back in evolution." (p.10) For Donald, the words "consciousness" or "awareness" encompass many phenomena. The first is mental states such as sleep, wakefulness, and alertness. Second, consciousness is a central executive in the mind -- a self-regulating high-level processor that receives input from many sources, examines it, and directs action based on analysis. This form of consciousness is what we sometimes call thought or understanding. Functionally, such consciousness is domain-general processing power, attention, and general-purpose skill that can be brought to bear on unfamiliar or complex tasks. Finally, the third form of consciousness "has more to do with enlightenment, or illumination, than with mere attention," playing upon human symbolic capacity rather than just attention.

Fundamentally, Donald's theory of consciousness is quantitative rather than you-have-it-or-you-don't. Beings (animals so far as we know, but in principal computers as well) can be more or less conscious. Their conscious capacity can support more or less information. They can handle problems of varying levels of complexity. They may have the first form of consciousness but not the other two, and so on. With this backdrop, Donald allows many animals into "The Consciousness Club," starting with creatures like ants and bees which can construct a representation of the world divorced from their immediate sensory input. At progressively higher levels of consciousness are fish and vertebrates, birds, mammals, primates, and humans. Further, not all humans share the same level of consciousness, and a child becomes more conscious as she develops. Despite the views of some philosophers, and perhaps common sense, consciousness isn't like a light switch. Furthermore, more consciousness is not always better. Awareness comes at a resource cost, and most animals are able to thrive in their ecological niche without much consciousness.

Donald then presents the evolution of human consciousness.

He groups the constituents of consciousness into three "levels of awareness."

• The first, associated with the sensory cortex, is binding or perceptual unity, the ability to combine perceptions to perceive complex phenomena like objects and events. This is the domain of "raw feeling."

• Level-2 awareness, which developed with the secondary cortex, is the domain of short-term memory and control. Here, birds and mammals have a sense of time and can focus on both an immediate perception and something which is out of sight but no longer out of mind. Such animals can also use their conscious power to learn new skills and create a new subconscious demon for them.

• Finally, humans and some other primates possess level-3 awareness, courtesy the tertiary cortex. We are able to maintain intermediate-term awareness, at the level of minutes or hours. We are able to perceive, dissect, and act upon very complex situations and events, and several of them at once. Level-3 is episodic awareness, as described in Origins.

Donald makes a big deal out of the intermediate-term awareness afforded by level-3 awareness. Results from clinical research indicate that people are remarkably limited in the here-and-now. The "seven plus or minus two" rule for short-term memory, its rapid degradation, and other findings understandably fuel the reductionist Hardliners. But Donald illustrates common human activities that seem to break these constraints demonstrated in the lab. In an ordinary conversation, a person may track far more than 9 things, including major points made by each speaker, rebuttals that have already been made, facts about the subject matter in question, points she has thought to make when the right opportunity presents itself, and so on, all on a scale of tens of minutes or even hours. Donald's example adds to the cognitive load even more by supposing that the conversation participants don't all share a common language. The intermediate-term is the domain of consciousness, which is brought to bear in everything from reading a book to pursuing a goal in the face of obstacles. In such a home, consciousness can coexist with fast, specialized modules for basic and time-critical tasks because their work is separate but linked.

Level-3 awareness is not sufficient for symbolic thought and culture, as Donald demonstrates with the examples of enculturated apes. Humans departed from their primate cousins, Donald thinks, by developing a superplastic brain and complex webs of culture, neither of which can feasibly exist without the other. "Deep" or "cognitive" enculturation is thus added to genes and environment as a driving factor of development. Deep enculturation, unlike the basic social environment, can alter the cognitive architecture, installing new modules and demons.

To demonstrate his point about deep enculturation, Donald leads the reader through the Condillac's statue thought experiment. Condillac asked his readers to imagine how a statue granted limited sensory power (such as just smell or smell, sound, and vision) would learn about the world. Condillac concluded that only once the statue had the powers of touch, action, and internal sensation (even without the other four senses) could it become fully conscious and thus understand the world in anything resembling a human way. "This," says Donald, "conveys one central tenet of Constructivism: Action begets self-knowledge."

Donald then presents a real-world "statue" in the story of Hellen Keller. After a year and a half of normal infant development, Keller lost her senses of sight and hearing, restricting her cognitive development for several years. Keller could communicate mimetically, modulated by her range of possible inputs, and had an internal model of the world, but couldn't communicate linguistically and had poor, if any, symbolic powers. After arduous attempts to teach her language through haptic sign language proved unsuccessful Keller's teacher, in a fit of frustration, signed "water" and then dunked Keller's hand in a bucket of water. This produced an epiphany as Keller realized the connection between symbols and her understanding and experience of the world. Symbolic capacity thus instilled, or at least linked to her sensory modality, Keller then quickly learned how to communicate linguistically through both haptic sign language and braille. She went on to lead a life of educated success that people with all normal senses would find quite challenging.

The example of Hellen Keller provides, in one glimpse, an understanding of Donald's arguments against modularity of high-level language and symbolism and in favor of deep enculturation and the mimetic/symbolic divide. Keller acquired language several years after most children and through several modalities, none of which were evolutionarily expected. Her superplastic human brain adapted to her unique experiences to allow her to lead a cognitively normal, if perceptually limited, human life. Since there is no selection pressure for the deaf and blind to learn language, the modularist has quite a bit of work to do to explain how Keller was able to develop skilled and full-fledged language.

The final two chapters of AMSR present a condensed version of the three transitions Donald describes in Origins, this time with an eye toward consciousness. I felt that these chapters provided an easier understanding of the key concepts of Origins, though I may have found it thus because I'd already understood Origins, and this section was mostly focused review. The material in these chapters is mostly covered in the above summary, so I will not repeat them here."

(https://trevorstone.org/school/donaldreview.html)

Review

Trevor Stone:

In stark contrast to the Hardliners, Donald says precious little about selfish genes, selection pressures, fitness maximization, or other concepts typically associated with the evolution of specific features and abilities. Though not often made explicit, Donald takes an emergentist and mosaic approach to human cognitive evolution. While making clear that consciousness and culture must have developed through biological evolution, he is careful to avoid any implicit teleology. Readers may be frustrated by Donald's lack of explanation and speculation on, for instance, why increased brain size at the expense of increased childbirth fatality improves fitness. However, there is no reason to suppose that most of the capacities Donald discusses have just one effect on fitness. In fact, Donald's view of the human mind demands just the opposite sort of explanation. If consciousness provides additional domain-general attention and processing power, it helps a wide variety of survival tasks from foraging to mate selection to personal defense to child care. In fact, the biggest strength of consciousness is its lack of adaptation to any specific function.

The benefit of describing capabilities instead of function is even clearer in the cultural realm. Once humans had mimetic skill, for instance, a whole host of activities were possible, producing many important consequences. Donald says that humans armed with mimesis can share information, model social structure, play games, perform group ritual, coordinate action, produce social conformity, teach skills, and develop innovative ideas. Each of these provides significant survival benefits, and there is no reason to label one of these as the function or an evolutionary driver of mimetic skill. A a group which develops mimesis has a better chance of surviving than one which doesn't because mimesis helps a group survive. More mimetic skill is better. No more grand explanation is needed.

The temporal order of cultural adaptations isn't particularly important, either. Michael Chwe describes how public ritual creates "common knowledge." By this term Chwe means not only shared information, but also the knowledge that other people know that the information is shared. Such common knowledge is vital to coordination problems, where people will only participate if others do. He points out that rituals in which everyone stands in an inward-facing circle and can thus see each other provide an optimal circumstance to build common knowledge. It doesn't matter much whether societies adapted circular rituals to solve coordination problems or whether they were first used just as "pure" information vehicles, circular so that everyone could see the performer. Regardless of which was the "reason" why group ritual evolved, we must describe both functions, as well as the sense of spiritual fulfillment and other logically subsequent effects, in order to fully explain why people participate in ritual.

This is most clear in the examples of coordination problems in modern ritual that Chwe presents. He shows that a disproportionate number of advertisements during the Super Bowl are for goods and services which face a coordination problem. (Most) people don't watch the Super Bowl so that they can obtain an advantage in coordination problems; they watch for entertainment. But nonetheless, coordination problems have a big part to play in this modern-day mimetic ritual, even if each person watches the game alone.

The example of group coordination helps show the level of evolution Donald thinks produced language and other coordinating cultural webs. He proposes that competition between hominid subspecies "for roughly the same, huge ecological niche," and the general challenges of social coordination imposed by such a conflict, provided selection pressure for language. This "survival of the tribe" view, rather than individual or family fitness, is appropriate for a common-good like coordination or language. The value of an ability for coordinated action increases as the number of other potential cooperators increases. A big-game hunter is more effective if he can communicate and coordinate with other would-be hunters, regardless of their genetic similarity. Language is more useful to a person when more people share that language, even if their interests are otherwise opposed. Among hominids, an individual's fate is closely tied to that of the group -- a superstar alone is largely helpless, and a less-than-stellar individual can survive and thrive when the group does well. The triumph of social factors over genetic ones in human survival is clear in modern warfare, where technical weapon-making knowledge and tactical strategy matter much more than any innate fighting skill. This sort of argument (unfortunately not clearly stated by Donald) can provide a firm basis for Donald's view of human evolution and development driven by culture.

* Expanding Consciousness

Perhaps the most radical piece of Donald's theory of mind is the role of the individual mind. He begins AMSR's 7th chapter by saying "We acquire our symbolic skills from the outside in. Therefore, we had to evolve them in the same way. Symbolic thought and language are inherently network phenomena. Thus their existence cannot be explained in a solipsistic manner. The problem calls for a paradigm shift, away from our mainstream theories of human evolution, which tend to assume that language evolved inside the brain box; that is, from the inside out." In this new paradigm, culture drives and humans respond. Symbols came first and humans learned to use them. That is, humans began using symbols and then internalized them.

Donald states "Collectivity has thus become the essence of human reality. Although we may have the feeling that we do our cognitive work in isolation, we do our most important intellectual work as connected members of cultural networks. This gives our minds a corporate dimension that has been largely ignored until recently." (AMSR, p. 298) In Donald's view it's not enough to describe what an individual person thinks. In order to fully describe human thought, we must describe culture, where each person plays a small role in constructing vast cultural concepts like myths, languages, customs, and common knowledge. This isn't a one-way street, either, where each person contributes to the product without the product influencing him as he would contribute to a tribe's total weight. Humans both produce and are produced by culture. Donald holds that culture directs human attention, determines what we learn, and mediates even our most private thoughts. Furthermore, very few of our thoughts are truly unique; we are mostly symbol manipulators and rarely symbolic inventors.

This isn't as radical of an idea as it might sound. Restated, it is essentially the point that ideas can be transmitted rather than merely generated from experience. In mimetic and mythic culture, people must still have the ideas in mind in order to do anything with them, though people can act as a group even if nobody has a complete mental representation of what's going on. It is, however, a departure from the Hardliner evolutionary psychology view that the human mind is programmed by genes and merely adjusts slightly to the local physical and social environment. For Donald, the adjustment is what programs the mind.

Donald's view of the external memory field challenges the "all in the head" view of cognition. Externally-stored symbols "change the long-standing relationship of consciousness to its representations." Unlike internal representations, external symbols are easily rearranged, reformatted, and related; can provide more (and more exact) detail; don't (usually) degrade over time; and (most importantly) are easy to organize for future retrieval. By using the right external representation, the human mind can offload most of the computation to the very structure of the information. A human faced with determining the correlation between, for instance, past and present population would be hard pressed to hold all of the data in working memory, let alone figure out the connection. But by simply graphing each piece of data, anyone can (literally) see the exponential nature of growth. Furthermore, by merely drawing a line between points on the graph, a person can make a sophisticated guess about an unknown data point. The external medium supports the brunt of this work -- the same person would have trouble coming to the same conclusions with a table of data pairs.

Donald states that "the locus of attentional control can reside, at least temporarily, in external memory" (Origins p. 372). By this and his examples, I take it he means that media like television can determine the object and flow of our awareness, a fact clear to anyone who watches a well-made film. This does not mean, as I understand it, that that thing which is attentive, and hence conscious, is anywhere outside of the person. Consciousness remains in the head, but some cognition is offloaded to external media.

There is a sense in which reference to external media isn't cognitively very new. Consulting a book isn't that much different than consulting an expert in the flesh-and-blood. In both actions, the desired information is stored outside the agent's brain; it is then imported and either acted upon or stored. The mind doesn't need to adapt much to use external symbols, regardless of how innate we suppose the mind to be. Thus, to explain the vast success of external media-enabled human cognition, we must appeal to the properties of the media themselves and the strategies humans have developed to harness them. Alphabetic indexing may be the greatest cognitive advance since language, eclipsed only recently by World Wide Web search engines. ("Search Google" plays an embarrassingly central role in my own cognition.)

Donald points out that properties of external symbol systems significantly influence how helpful they are to cognition. He notes that the difficulty of learning written Chinese prevented widespread literacy and that certain kinds of math are impossible with Roman numerals. However, the particular media of external representation may have a much more profound impact on thought than Donald lets on. Leonard Shlain traced how, throughout recorded history, the cultural arrival of alphabetic literacy co-occurred with ideological violence, suppression of women and feminine values, destruction of images, and a masculinization and monotheitizing of the culture's mythology. Furthermore, as photography and electromagnetic technologies spread, cultures became more ideologically tolerant, women's rights and values were honored, words became less powerful than images, and polytheistic feminine deities reemerged.

Shlain suggests an explanation that has one foot in metaphor and one in neuroscience to describe the counterpunctual interplay between alphabet literacy and "masculine hunter/killer values" on one hand and images and "feminine gatherer/nurturer values" on the other. The cognitive and neurological skills needed for reading and writing depend on predominantly "left brain" skills such as serial directed focus, abstract thought, and precise motor control of the right hand -- the same sorts of skills hunters and fighters must rely on. Image processing, on the other hand, relies on "right brain" functions like holistic and gestalt perception and concrete thinking -- the skill set needed by gatherers and caretakers. Metaphorically, therefore, a culture saturated with writing experiences is dominated by a collective hypertrophic left brain. Anecdotally, this mirrors my own cognitive development. When I was younger I held disdain for photography, movies, and art while harboring a desire to forcefully convert those who I thought held wrong beliefs or who did things in the "wrong" way. However, as I started watching more movies and seeing more images (largely on the World Wide Web), I became much more tolerant of other ideas and ways of doing things. These cultural and personal perspectives suggest that the external media, regardless of content, strongly influences the way people think. This isn't limited to theoretic culture and external media, of course; the same information, such as a message of trust, will be received and acted upon differently if it's conveyed mimetically versus orally.

The description of collective consciousness sounds rather like a computer network, where each computer can receive programs, instructions, and data from the network and respond in kind. Unfortunately, Donald seems uninterested in computers -- the references for AMSR contain but a few pointers to the literature, and he doesn't restate his response to Lutz that I cited earlier. As a well-understood domain, computer networks may help us understand the hazier aspects of human cultural interactions, especially from an emergentist framework. Furthermore, given Donald's view of culture as an active and powerful force in shaping cognition, it may be possible for a computer culture to emerge, producing symbolic capabilities that have largely eluded even the most diligent artificial intelligence researchers. How much of the human cognitive suite would computers need to produce and be produced by culture?

The research area known as Distributed Cognition primarily focuses on small groups of people and their work environment, such as an airplane cockpit or an office. However, their exploration of principles such as collective action with distributed knowledge and human-computer interaction could prove illuminating if applied to the distributed cognition of an entire society that Donald describes. Can we think of computers as our own "mental modules?" What about other people? We send them input and act on the output they provide. Is there a distinct hybrid culture of people plus computers that neither human nor computer societies produce on their own?"

(https://trevorstone.org/school/donaldreview.html0

More information

See the other, earlier, book by the same author:

• Origins of the Modern Mind: Three Stages in the Evolution of Culture and Cognition. By Merlin Donald. 1991