Evolution of Cognition

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* Paper: The Evolution of Cognition. William L. Benzon and David G. Hays. Originally published in Journal of Social and Biological Structures 13(4): 297-320, 1990

URL = http://asweknowit.ca/evcult/CogEvol.shtml


"With cultural evolution new processes of thought appear. Abstraction is universal, but rationalization first appeared in ancient Greece, theorization in Renaissance Italy, and model building in twentieth-century Europe. These processes employ the methods of metaphor, metalingual definition, algorithm, and control, respectively. The intellectual and practical achievements of populations guided by the several processes and exploiting the different mechanisms differ so greatly as to warrant separation into cultural ranks. The fourth rank is not completely formed, while regions of the world and parts of every population continue to operate by the processes of earlier ranks."


Cognitive Rank

"Cognitive rank is about the conceptual tools a culture has for the elaboration of abstract thought. People in all cultures reason abstractly, for that capacity inheres in language (see Benzon and Hays, 1988). But cultures differ in their capacity to order and generate abstract concepts. There are abstract ideas that cannot occur in the thinking of an Eskimo, or even a literate Florentine, or, for that matter, Darwin, Freud or Einstein. And, since there is no reason to believe that cognitive evolution has, or is about to, run its course, abstract ideas will be created which cannot occur in the most sophisticated systems of thought in current use.

The question of cognitive evolution is motivated by the observation that, of the many ways in which cultures differ from one another, complexity is one of the most obvious. An extensive body of research (Levinson & Malone, 1980) shows that when cultures are compared with respect to such things as number of levels of political organization, population of the largest community or of the whole polity, division of labor (number of crafts, technological diversity), external commerce, means of enforcing justice and equity, social stratification (caste and class), character of religion, legitimation of government, use of machinery, sources of power, kinds and amount of transportation, extent and quantity of communication, kind and amount of capital investment, some cultures have more than others. Further, the cultures which are more complex in one arena tend to be more complex in the others as well. The most obvious route to such differences is evolution: the more complex cultures emerged from the less complex by some evolutionary process.

Cognitive evolution, however, is not only about complexity; it is about sophistication as well. The arithmetic procedures we have been using since the Renaissance aren't more complex than those used by the Greeks and the Romans. They are, in fact, simpler. They are also more sophisticated and thereby much more effective. The cognitive processes of a culture of a high rank are more sophisticated than those of a culture of lower rank.

In dealing with this complexity and sophistication we need to avoid the racism which characterized nineteenth century thought on cultural evolution. Racism was intellectually respectable then and nineteenth-century thinkers really had no intellectual alternative. They thought that cultural evolution required better thinking, as indeed it does, and could ascribe improved thinking only to better brains. They had no theory of information, of learning, and were nowhere near the essential theory of learning to learn, which is the crucial link between cognition and cultural evolution.

The Nineteenth-century racists could not distinguish between culture and biology and assumed that cultural differences had to be explained by biological differences. But culture is a realm of being unto itself. Its phenomena cannot be reduced to biological phenomena. Hence a theory of cultural evolution need not imply anything about the relative merits of one gene pool over another. Cultural evolution isn't about biology; it is about culture. Cognitive evolution, as we see it, is a component of cultural evolution.

Yet there must be a biological substrate for culture. The possibility of culture, perhaps even its necessity (see Geertz, p. 1973), is inherent in human biology. The brain is the most obvious locus for our capacity for culture. The brain makes language possible and, by implication, culture. It is through language that humans elaborate their perceptual, motivational, navigational, and manipulative abilities into the complex mechanisms of culture. Language makes us capable of abstract thought, of conceiving, caring about, and inculcating such things as mana, gravity, justice, electromagnetism, and so forth. All cultures deal with abstractions but, as a culture evolves, the diversity and depth of its abstractions increases.

We are here concerned with characterizing this growth in abstractive power. This growth does not require any biological change. It requires only language. Any language which is a human language contains within itself the mechanisms necessary for evolutionary growth. In fact, it is probably more subtle than this. Whatever it is about the brain which makes language possible, that is the engine behind culture (see Benzon & Hays, 1988). That is a subtlety, however, which does not affect the main thrust of our argument.


The basic idea of cognitive rank was suggested by Walter Wiora's work (1965) on the history of music. Wiora argued that music history be divided into four ages. The first age was that of music in preliterate societies and the second age was that of the ancient high civilizations. The third age is that which Western music entered during and after the Renaissance. The fourth age began with this century. (For a similar four stage theory based on estimates of informatic capacity, see Robertson, 1990.)

This scheme is simple enough. What was so striking to us was that so many facets of culture and society could be organized into these same historical strata. It is a commonplace that all aspects of Western culture and society underwent a profound change during the Renaissance. The modern nation state was born (Gellner 1983), the scientific revolution happened (Butterfield, 1957; Cohen, 1960), art adopted new forms of realistic depiction (Gombrich, 1960), attitudes toward children underwent a major change (Aries, 1962), as did the nature of marriage and family (Stone, 1977), new forms of commerce were adopted (Braudel, 1981-1984), and so forth. If we look at the early part of our own century we see major changes in all realms of symbolic activity--mathematics, the sciences, the arts--while many of our social and political forms remain structured on older models.

The transition between preliterate and literate societies cannot easily be examined because we know preliterate societies only by the bones and artifacts they've left behind, and the historical record of the ancient high civilisations is not a very good one. Instead we have to infer the nature of these ancient cultures by reference to modern anthropological investigations of preliterate cultures (just as biologists must often make inferences about the anatomy, physiology, and behavior of extinct species by calling on knowledge of related extant species). When we make the relevant comparisons we see extensive differences in all spheres.

Social order in preliterate societies may involve nothing more than family relationships, or at most the society extends kinship by positing ancient common ancestors. With little or no apparatus of government, civil order is maintained by feud or fear of feud. In literate societies, social order is kept by etiquette, contract, and courts of equity, and civil order is maintained by police and courts of justice. In preliterate societies each community, of 5 to 500 members (and generally less than 200) is autonomous until (about 6000 years ago) chiefdoms appear in a few places, and groups of villages forced into submission (Carneiro, 1981). In literate societies villages grow into towns and cities, which organize the villages of their hinterlands into kingdoms. Preliterate societies depend on the skills of hunting and gathering, of slash-and-burn farming, pottery, and a few more crafts, which are sound and effective where they exist. In literate societies certain persons trained to think choose to think about farming and write manuals for the agrarian proprietor--and eventually manuals of other crafts appear. Finally, Lawrence Kohlberg (1981, pp. 128 ff., 233 ff.) has found evidence that people in preliterate societies have less sophisticated moral concepts than people in literate societies.

The appearance of writing was followed by the Mosaic law and the prophets of Israel, and by the Periclean Age in Athens. The architecture, democratic political system, and above all the philosophy--both natural and moral--of the Hebrews and Greeks was so different from all predecessors that we tend to think of our civilization as beginning with them. In fact, a period of cultural regression followed the fall of Rome and before the Renaissance could begin a "little renaissance" beginning about A.D. 1000 and reaching its peak with Aquinas in the 13th Century was necessary to raise Europe once more to a literate level. Our civilization combines elements of Greek, Roman, and Hebrew antiquity with Moslem, Indian, Chinese, and Germanic elements.

We are suggesting that these four ages, the systematic differences between cultures at these four levels of cultural evolution, are based on differences in cognitive mechanism. As cultures evolve they differentiate and become more complex and sophisticated, the more sophisticated cultures having cognitive mechanisms unavailable to the less sophisticated. Over the long term this process is discontinuous. That is, at some point in the evolution of a culture a new kind of thinking becomes available which permits a dramatic reworking of culture. This new kind of thinking is engendered by a new capacity for manipulation of abstractions.

These several kinds of thinking are cumulative; a simpler kind of thinking does not disappear from a culture upon the introduction of a more complex kind. A culture is assigned a rank according to the highest kind of thinking available to a substantial fraction of its population (cf. Kohlberg, 1981, p. 129). That a culture is said to be of Rank 3 thus doesn't imply that all adult members have a Rank 3 system of thought. It means only that an influential group, a managing elite if you will, operates with a Rank 3 cognitive system. The rest of the population will have Rank 1 and Rank 2 conceptual systems.

Each cognitive process is associated with a new conceptual mechanism, which makes the process possible, and a new conceptual medium which allows the mechanism and process to become routine in the culture. This is an important point. The general effectiveness of a culture is not determined by the achievements of a few of its most gifted members. What matters is what a significant, though perhaps small, portion of the population can achieve on a routine basis. The conceptual medium allows for the creation of an educational regime through which a significant portion of the population can learn effectively to exploit the cognitive process, can learn to learn in a new way.


The vast majority of the world's cultures have Rank 1 cognitive systems. All of the cultures indigenous to North and South America, sub-Saharan Africa, Australia, Polynesia and Micronesia, Siberia, and the hill country of Southeast Asia are Rank 1 cultures. Rank 1 cultures are very diverse because the evolutionary criterion--effectiveness--is relatively lax in the demands it makes on culture patterns. The range of things a people must do to ensure their physical survival is relatively narrow in comparison to the mind's need and capacity to bring conceptual order to the world. The collective cultural inventiveness of Rank 1 cultures far exceeds the requirements of physical survival. The number of distinct and independent Rank 1 cultures thus numbers in the thousands.

There have been only 3 or 4 independently arising Rank 2 cultures, the rest all arising through diffusion or conquest. Around the eastern Mediterranean, from Egypt and Mesopotamia up through the Hebrews and Greeks to Rome: that is one. Harappan civilization in the Indus basin: that is two, but with possible linkage to the eastern Mediterranean. China: that is three, and the possibility of remote linkage exists there as well. Islam is perhaps regressive, and altogether derivative. Muscovite and Byzantine are derivative as well. By our standards the American cultures (Aztec, Mayan, Inca) did not quite reach rank 2.

The range of diversity among Rank 2 cultures is high, but perhaps not so high as that among Rank 1 cultures. Rank 2 polities, however, are more internally diverse than Rank 1 polities, in part because many Rank 2 polities have incorporated a variety of Rank 1 polities through conquest.

Rank 3 cognition happened, independently, only once, in Western Europe during the period called the Renaissance. It remains to be seen whether or not, or in what sense, Rank 3 culture admits of variety. Certainly in one respect, science and technology, there is only one Rank 3 culture. But, is democracy of one sort or another the only viable rank 3 political system? Possibly the Rank 3 contents of culture are so constrained under the force of three mechanisms of abstraction that there is no variety possible--or perhaps possible, but not obvious.

Edwin O. Reischauer's (1977, p. 288) remark that we should think of Japan as becoming modernized, as opposed to becoming Westernized, suggests that Japan is evolving a Rank 3 culture which is, in many respects, different from the Rank 3 culture of the West. Perhaps, for example, we should think of the much-studied Japanese corporation (Ouchi, 1981; or Halberstam, 1986) as a non-Western way of organizing Rank 3 business and manufacturing tasks. Within the United States, the emergence of jazz provides a different example. Jazz is quite different from classical, or European (and European-derived) music, and some authorities maintain it has a sophistication and expressive power which is equivalent to classical music (Collier, 1978; Williams, 1983). If so, then jazz is a Rank 3 music which is quite different from the Rank 3 music of Europe, suggesting that Rank 3 culture isn't restricted to the lines of development implicit in Western Europe of the Renaissance.

As far as we can tell Rank 4 culture exists only in various intellectual and artistic realms. The earliest teaching of rank 4 was presumably in a few graduate departments of physics and mathematics. After World War II, a few other disciplines reached that level, but only in certain universities. In the proliferation of new "interdisciplinary" ventures one can readily distinguish between those that combine elements of two recognized disciplines without generating much that is new, and those that lay out two disciplines side by side only to transcend them; the latter are likely to be teaching Rank 4 ideas. In the 1980s, several graduate schools of management adopted curricula incorporating such things as operations research, decision theory, and game theory in a way that rises above Rank 3. The remarkable suggestion, made by the government of the USSR in 1989, that a world-wide referendum determine whether East and West Germany could reunite, gives some hint of what might be expected in a Rank 4 political system. Twenty years ago, most countries claimed that human rights were a matter of national sovereignty; more recently, many countries have agreed that suppression of rights anywhere is a matter of universal concern." (http://asweknowit.ca/evcult/CogEvol.shtml)

Rank 1: What's In a Name?

Rank 1 cultures run the gamut from simple roving bands of hunter-gatherers to quasi-states living in large permanent settlements. The peoples living in the Americas when the Europeans first arrived are all Rank 1 cultures, from roving bands which followed the buffalo in the central plains of North America to the Aztec, Maya, and Inca empires. The range of complexity across these societies is great, but all are within the compass of Rank 1 cognitive mechanism.

The emergence of language catalyzed the emergence of Rank 1 culture. What is critical about language is that it enabled people willfully to manipulate their mental processes, to gain control of consciousness (see Jerison, 1976, Vygotsky, 1962; Csikszentmihalyi, 1990, discusses the manipulation of consciousness in a way which is relevant here). With language people can call up thoughts of events long past and far away, thoughts of events which haven't happened yet, even stories about purely imaginary beings and deeds. Through language it is possible for an individual to summon a multiplicity of concepts and images to mind in a relatively short time and to bring the mind's synthesizing and analytic capacities to bear on this multiplicity. In ten minutes, a half-hour, an hour, more or less, a story can cover a much greater range of experience than would be accessible in the same period of time if one had to go there to see, hear, taste, and do it, whatever the "it" might be. In a short time one can tell a story which ranges across the entire geography inhabited by one's culture. But to travel that territory might take days, or weeks, or more.

Much of the abstract knowledge of Rank 1 cultures is carried in myth. Levi-Strauss (1969) has shown that, however bizarre the events of a myth may seem to us, myth is governed by a rigorous and relentless logic in which schemes of kinship, geography, the satisfaction of biological needs, and cosmography are subject to the same ordering principles."

Rank 2: The Letter of the Law

Writing is critical not only because it allows the stable representation of thoughts but also because it forces thinking about thought. In contemplating the written word, scribes and sages begin systematically to think about words, the sequencing of words, and, inevitably, about the mental processes behind words, about thought. They were able to do this because they could see a text as a whole, they could get outside the flow of discourse as no illiterate speaker or hearer could do. They had to do this in order to create and refine the conventions of written discourse. For writing imposes much stricter requirements of completeness and grammaticality to make up for the lack of paralinguistic and contextual clues available in face-to-face conversation, not to mention the ability to question the speaker about anything one doesn't understand. The writer is inherently more self-conscious than the speaker and such self-consciousness is likely to engender thought about writing, language, and ultimately, about thought itself.

While the capacity to formulate discourse about language is intrinsic to language--Roman Jakobson (1961) called this the metalingual function--the use of writing facilitates such metalinguality. With writing the text becomes a sense-data entity of a much more palpable sort than the airy nothings which carry speech from tongue to ear. Metalinguality thus can first be about the text, and then by abstraction about the language and the thought that the text represents. The problem of creating and using a writing system thus moved metalinguality to the point of engendering a new process of thought, rationalization, through the form of metalingual definition.

Recall the analysis of charity. "Charity" could be given meaning by recounting various instances of charity, just as "apple" can be given meaning by pointing to various instances. The rationalization, "when someone does something nice for someone else without thought of a reward," expresses an abstraction over the collection of exemplifying instances. The use of such rationalizations is what we are asserting is new to Rank 2 culture. People in Rank 1 cultures have abstractions, but have only proverbs and myths for expressing them. The mechanism of metalingual definition allows a Rank 2 culture explicitly to convey its abstract knowlege through rationalizations. With conveyance comes the possiblity of intellectual analysis, of philosophy, and of mathematics as well.

With the emergence of philosophy comes the explicit construction of ontology. In his Categories Aristotle states that all assertions are about substance, quantity, quality, relation, time, position, action, or passivity. These categories constitute an ontology, an assertion of the main aspects of reality. In his treatise On the Soul Aristotle analyzes the soul as a substance and argues that it has a hierarchy of functions: the nutritive, the perceptive, the locomotive, and intellective. Living things can be arranged in a hierarchy according to how many of these faculties each possesses, thus giving us an account of the varying capacities of plants, animals, and humans.

The Rank 2 abstractive system thus has two mechanisms available to it: metaphor and metalingual definition. Metaphor, the basic mechanism for managing abstraction, rides at the "top" of the system, as it did at Rank 1, and brings new abstractions into awareness. The metalingual mechanism rationalizes the ontology implicit in the relationships between objects and events in the concrete domain. This yields the categorical thinking of Rank 2 philosophical thought. The world is distributed into a set of categories--which, in the West, became the Great Chain of Being--and explanations are formulated in terms of these categories. Each thing acts in accordance with the capabilities of its category. The problem is to determine its category and assimilate its actions to the capacities inherent in its category.

Consider how much of philosophy is devoted to the definition of terms, to rationalizing their meaning."

Rank 3: Subject and Object

"The role which speech plays in Rank 1 thought, and writing plays in Rank 2 thought, is taken by calculation in Rank 3 thought (see Havelock, 1982, pp. 341 ff.). Writing appears in Rank 1 cultures and proves to be a medium for Rank 2 thinking. Calculation in a strict sense appears in Rank 2 and proves to be a medium for Rank 3 thinking. Rank 2 thinkers developed a perspicuous notation and algorithms. It remained for Rank 3 thinkers to exploit calculational algorithms effectively. An algorithm is a procedure for computation which is explicit in the sense that all of its steps are specified and effective in the sense that the procedure will produce the correct answer. The procedures of arithmetic calculation which we teach in elementary school are algorithms.

These procedures are so familiar to us, and so obviously elementary, that we forget that their creation was a major cultural achievement--attempting long division in Roman numerals, however, should remind us of just how very difficult computation can be without a good system of notation. Nor did the ancients have explicit rules of procedure. Marrou, in describing education in the Hellenistic period, writes (1956, p. 158):

Strange though it may seem at first, it is nevertheless quite clear that addition, subtraction, multiplication and division ... were, in antiquity, far beyond the horizon of any primary school. The widespread use of calculating-tables and counting-machines shows that not many people could add up--and this goes on being true to a much later date, even in educated circles.

In an additional note (p. 410), Marrou remarks that adults would often write out multiplication tables for themselves, presumably because they could not obtain answers out of their heads. Without a good system of notation the formulation of algorithms is so difficult that a complete set wasn't created for any number system other than the Indo-Arabic. Before these procedures were gathered and codified the calculations our children routinely make required the full attention of educated adults, who solved them on a case-by-case basis (Childe 1936/1951, pp. 152-153):

The mathematical texts are simply concrete examples of different problems worked out in full. They illustrate to the reader how to do sums of various kinds. But by themselves such series of examples could hardly suffice to enlighten a novice as to new methods nor impart to him fresh knowledge. They must have been intended as supplements to oral instruction.

But Childe has no evidence about the oral instruction, and Marrou seems to believe that there was none. In the twentieth century we have taught psychiatry, business management, and the law by the method of case study. What has to be accepted as fact--however "Strange though it may seem at first"--is that up to the Renaissance elementary arithmetic was taught in just that way, and, we hold, for the same reason: The kind of thinking that was available in the culture could just manage the substance of the matter but could not rise above it to abstract and rationalize the principles.

The algorithms of arithmetic were collected by Abu Ja'far Mohammed ibn Musa al-Khowarizm around 825 AD in his treatise Kitab al jabr w'al-muqabala (Penrose 1989). They received an effective European exposition in Leonardo Fibonacci's 1202 work on Algebra et almuchabala (Ball 1908). It is easy enough to see that algorithms were important in the eventual emergence of science, with all the calculations so required. But they are important on another score. Algorithms were the first purely informatic procedures which had been fully codified. Writing focused attention on language, but it never fully revealed the processes of language (we are still working on that). A thinker contemplating an algorithm can see the complete computational process, fully revealed.

The amazing thing about algorithmic calculation is that it always works. If two, or three, or four, people make the calculation, they all come up with the same answer. This is not true of non-algorithmic calculation, where procedures were developed on a case-by-case basis with no statements of general principles. In this situation some arithmeticians are going to get right answers more often than others, but no one can be sure of hitting on the right answer every time.

This ad hoc intellectual style, moreover, would make it almost impossible to sense the underlying integrity of the arithmetic system, the display of its workings independently of the ingenious efforts of the arithmetician. The ancients were as interested in magical properties of numbers as in separating the odd from the even (Marrou, pp. 179-181). By interposing explicit procedures between the arithmetician and his numbers, algorithmic systems contribute to the intuition of a firm subject-object distinction. The world of algorithmic calculations is the same for all arithmeticians and is therefore essentially distinct from them. It is a self-contained universe of objects (numbers) and processes (the algorithms). The stage is now set for experimental science. Science presents us with a mechanistic world and adopts the experimental test as its way of maintaining objectivity. A theory is true if its conceptual mechanism (its "algorithm") suggests observations which are subsequently confirmed by different observers. Just as the results of calculation can be checked, so can theories.

In this respect, theory differs from definition. The test of a definition is that it suffices for the cognitive process of rationalization. The thinker explores a network of definitions, from charity to reward, from reward to the abstractions needed in defining it, and so on step by step. If this expansion leads to a sense of satisfaction, perhaps specifically a sense of coherence, then the thinker accepts the new definition, and claims to know what charity is. The thinker may also be able to decide whether a specific incident is an act of charity. But the process of exploration is not under the overt control of the thinker--it is meditation, not calculation. The thinker who has an algorithm does not enact it or meditate on it, but executes it. From this difference in process follows the fact that theories can be checked--the observations and calculations of different workers can be compared--but not definitions."

Rank 4: Modern, Post-Modern, and All that Jazz

Two decades ago counter-cultural savants in the West proclaimed the coming of an Aquarian Age. A decade ago different savants eagerly anticipated the emergence of an Information Age (Toffler, 1973). Is this just millenial fever triggered by anticipation of the turn of the next millenium--as years ago our European ancestors anticipated the second coming of Christ with approach of the year 1000--or is something really happening?

There is no definitive way of refuting the view that nothing is happening. But, those who maintain it must at least admit that, in the past, there have been major changes in culture and so such changes are at least possible. At the very least, those who argue that we are undergoing some form of radical change are not arguing for something we know has never happened.

We are of the view that, once again, culture is evolving toward a new rank and that most of the intellectual and artistic displacement we are seeing reflects these growing pains. This new cognitive rank, Rank 4, has its origins in two developments in late nineteenth century thought: the creation of formal systems of logic and metamathematics and the emergence of non-mechanistic science.

The metamathematical work of the late nineteenth and early twentieth centuries was intended to provide rigorous deductive foundations for all branches of mathematics and to unify these branches into one coherent system. The work in logic was concerned, on the one hand, with developments in mathematics, but was also concerned about formulating general mechanisms for the formulation of any type of proposition so that the propositions of science could be formulated in a giant deductive system from which truths could be cranked out on a routine basis. Thus the development of the propositional calculus and set theory, whatever their importance for metamathematics, also looked toward the world and got some thinkers into the habit of translating propositions from ordinary language into logical forms. Thus logic became a set of formal tools in which other conceptual systems--mathematical and scientific--could be represented. As the physical sciences moved more abstractly into the physical world, logic moved more abstractly into the informatic world.

The new scientific style was forced further and further from a mechanistic universe by hard facts of the most intransigent and nonmechanistic sort. Thermodynamics provides the prototype, with biology (evolution) right behind (Prigogine & Stengers, 1984). Perhaps the most deeply unnerving case, however, is that of quantum mechanics. That light behaved in some experiments like waves and in other experiments like particles was uncomfortable. To explain what they could see, physicists had to imagine a quantum world that they could not see: In principle and not in mere practice, the quantum world is not observable (Penrose, 1989). Yet it provides a framework for mathematical derivations that explain, if that is the right word, the observations that can be made in our world. The fact of the matter is, Rank 4 science is as different from Rank 3 science as Rank 3 science is from Rank 2 natural philosophy. Sophisticated logic and mathematics become ever more necessary to thought. To admit the forces and the intangible particles without logic and mathematics to regulate explanation would be to readmit magic and superstition.

Time itself comes under new scrutiny. Not until the turn of the 20th century was motion was studied in enough detail so as to provide descriptions of complex irregular movement. Motion pictures, photographs showing the paths taken by hands performing a task, time-motion studies in factories, and paintings of a single subject at several stages of an action all turned up more or less together. This conceptual foregrounding of temporality, when combined with metamathematical and logical reasoning, led to the development of the abstract theory of computing between the world wars.

The central work is Turing's explication of the algorithm. Rank 3 had concocted and used algorithms, but Turing explained what an algorithm was. In order to formulate the algorithm Turing had to think explicitly about the control of events in time. He described his machines as performing an action at a certain time; then another action at the next moment; and so on for as many consecutive moments and actions as necessary. His universal machine, a purely abstract construction, was an algorithm for the execution of any algorithm whatsoever. With it, he showed that no interesting formal system can be complete in the sense of furnishing a proof for every true statement. (Others reached the same conclusion by other methods, and he missed being first by a brief interval.)

It took the work of von Neumann, and others, however, to embody Turing's account of the algorithm in a physical device: the computer (Bernstein, 1964, pp. 60 ff.). Of particular importance is von Neumann's use of the conditional jump as a control structure. In a computer all of the data and instructions are kept in a long list. The computer operates on this list by taking an item, operating on it, and then moving to the next item, operating on it, and so forth, item after item. For purely mathematical purposes such an arrangement is fine--it is how Turing thought of his abstract machines. For practical computing, however, this is not a good arrangement. For practical purposes you want to be able to access any piece of data, and any instruction, whenever you need it, regardless of whether it is next in line. There is no practical way of arranging things so that the next item needed is always the next one in line; you need to jump around. Von Neumann's conditional jump allows this. The basic idea is that one applies a test to the current state of the computation. Where the computation moves next depends on the outcome of the test. In principle the computation could move to any instruction and any piece of data regardless of where that item is; it need not be the next one in the list. Much of the art of programming consists in the ordering and manipulation of such control structures. From a purely mathematical point of view they are unnecessary. But without them there would be no practical programs, no art of programming. For this reason we think of control structure, starting with von Neumann's conditional jump, as the Rank 4 conceptual mechanism, corresponding to the Rank 3 algorithm and the Rank 2 metalingual definition.

Yet the thinker of Rank 4 is not a Turing machine but a user of both objective models and algorithmic theories of them. The way out of the impasse found by Goedel, Turing, and others is to remember always that it is possible to construct a new Turing machine to prove what the former could not prove. The loss of sense data as a faithful representation of reality on acceptance of quantum mechanics and the loss of total deducibility in metamathematics led to a crisis in Rank 3 thought. But Rank 4 can accept the situation and exploit it to obtain both the transistors and the programs of digital computers--pragmatic justification for Rank 4's extraordinarily sophisticated conceptual processes. Its models of nonobservable phenomena are useful." (http://asweknowit.ca/evcult/CogEvol.shtml)


Five Factors contributing to cognitive evolution

Terje Bongard:

"The human cognitive evolution was under the influence of five main areas:

1 Size difference of sex cells. The sex cell difference can be traced through the evolution of all organisms, and is an inevitable result of evolution: Either be few, large, immobile, nutritious and attractive, or many, mobile, small and competitive.

2 Natural and sexual selection. Darwin was the first biologist that was puzzled by the extravagant traits observed in nature. He described the difference between survival and attraction: There is no evolutionary reward in survival if no-one wants to mate.

3 The individual and the brain evolution. Each human being is the descendant of those who managed to compete, cooperate, maneuver and outwit. Humans are also an aggressive species, but the cognitive mechanisms reveal an evolutionary history of extensive brain selection.

4 Ingroup evolution. The family/ingroup brain selection has formed cooperation, dedication and empathy, which represent the best of us. The Handicap Principle is one of the evolutionary mechanisms that has provided us with generosity and warmth, and give hope for the organization of sustainable societies

5 Outgroup evolution. Suspicion, war and conflicts are the flip coin of the ingroup and evolution of the feeling that “our culture is the best.”


"There are three evolutionary mechanisms important for the ingroup - outgroup dichotomy: The Handicap principle, the Tragedy of the Unmanaged Commons, and Game theory."

(cfr. The Biological Human)