George Modelski


Department of Political Science

University of Washington


Prepared for the conference on


University of Lund, Sweden, March 25-29, 1995









If the question is: what explains the development of the world system over the past 5000 years of its history, then our answer is: world system development is the product of an evolutionary process, or better still, of an array of evolutionary processes.

We therefore propose here that world system history be examined in the first place as an incident in the evolution of the human species; world system is one form that the organization of humanity can assume, and clarifying it is one  way the boundaries of the concept can be ascertained. Secondly, we propose that the structural components of world system, such as economic, political, social, or cultural, are each subject to evolutionary processes, each of a distinct character but each subject to the same basic set of mechanisms. We assume finally that all of these evolutionary processes are not randomly scattered but rather exhibit synchronization of a co-evolutionary character.

Such a conception yields a number of conjectures about the shape and timing of world development. It is a conception that is especially fruitful for viewing the big picture of the behavior of the human species in the large; it yields a periodization of world history as a phased evolution of the world system; it serves as a way of ordering the growth of the world economy, and of world politics, and the accretion of a world community;  and for the last millennium of our experience it affords a finer-grained depiction of structural change at the global level, with especial attention to the rise of world powers. Miraculously, all these separate processes seem to be interdependent and well synchronized.

All of this is a theoretical conjecture that amounts to the spinning out of a few basic rules of evolutionary processes. But unlike 19th century schemes of evolutionism, it also purports to be capable of being tested. Correspondences between these conjectures and standard accounts of world history will be noted, and certain other supporting evidence will also be discussed. But the principal purpose of this paper is to lay out the basic logic of this argument, and the way in which all of it forms an interrelated, symmetric, and mutually supporting structure that in turn gains in strength from being grounded in evolutionary theory.

World system evolution is the story of humans learning to live with each other, and learning to do so in global proportions. It is the story not of a movement guided either purely by instinct or in accordance with a prearranged plan or toward a given end, but rather that of a continual and continuing search pursued in accordance with the laws of evolutionary process.


A process definition

Let us begin by establishing a definition of our basic term, world system, and make that a "process" definition. We define the rise of the world system as "the process of advancing the social and conceptual organization of the human species, actual or potential". In other words, our interest lies not in mapping the state of the world system at a point in time, but in gaining a conceptual purchase upon large -scale temporal social change.  Let us look at the implications of the several parts of that definition in greater detail.

On this view, world system is, in the first place, a form of species organization. A species is a population of individuals that interbreed and that share common attributes and a common fate; forming a complex system, it is a collection of organisms that is subject to evolutionary processes. Biologists inform us that the number of living species of animals on this planet is of the order of one million (Lumsden and Wilson 1981:4) and about each of these the question might be asked: how is that species organized, and how well is it organized? For by the condition of interbreeding alone, members of a species are intimately related, and share important symbioses that include forms of social organization. They signal in order to establish mutual recognition as members of the same species, they cooperate if only in the processes of reproduction; they experience competition and conflict, and they depend on certain resources in order to survive, and continue breeding.

But Lumsden and Wilson (ibid.,3-7) also argue that the human species is unique in the magnitude of its enculturation process. "Mankind has attained" the "complete" or "true" cultural state because its repertoire includes not only simple learning and imitation, but also complex learning: teaching linked to socialization of the young, and the employment of symbols by human agents. This creates the potential for more advanced forms of social organization.

World system is the product of these processes but it is, above all, a form of social organization, a structure (that is, a relatively long-lasting pattern) of social relationships. As social action we consider it for analytical purposes to be distinct from, though interrelated with, types of action systems that are psychological, cultural, or behavioral. The chief question we ask of this structure is not: does it exist, because we postulate that, in varying degrees, it does as an emerging and ongoing process; but how it changes. World system changes, or transformations, may then be seen as major shifts in the social patterns of the human species. But the focus of this analysis of world system is organization, and not culture as complex meanings and the codes that govern it, nor changes in the make-up of personalities, or the adaptations in the behavioral organism that mediate between the physical organism and human action.

As social organization , world system changes may, of course, be decomposed, on the vertical dimension, into global, regional, national, and local layers, and on the horizontal dimension, into their economic, political, societal, cultural (strictly-speaking, culture-reproductive) structures. In this sense, we might envisage a fully developed world system to comprise world economy, world political system, world community, and world cultural system, each of which might also exhibit global, regional,  etc. elements. These components are not randomly assembled; each occupies a distinct position in the world social structure.

We do not subscribe to an economic-determinist position that would view the economy, as division of labor, as the basic unit, but we might rank the economy as, in the shorter run, the most basic of these structures, followed by politics, society, and culture;  but we might also argue that those institutions that shape and transmit widely held values, are the most important for long-range social organization, followed by societal, political, and last of all, economic arrangements.

The empirical referent of world system are the networks of interactions linking the members of the human species. Such networks form the basis of the world system when they are potentially, or actually, planetary, or world-wide in scope.  Should humans come to settle other planets, but remain in contact with the Earth, then the pattern of their activities, and their relationships would also be comprised under the term of world system. But species-wide interactions are the property of the human species and antedate the world system. We do not, at one point, see a world system because we can point to the evidence of interactions; only if these interactions evince certain characteristics and a certain structure. That is, our primary task is not the mapping of interaction networks, and asking if they are world-wide, but rather the explanation of a learning process.

In its distribution, the human species has been world-wide, that is reaching every continent, for some time now, homo sapiens sapiens (anatomically modern humans) having expanded, probably on the basis of superior skills in communication by language, from Africa to every continent by, at the latest, 15,000 years ago (Asia, 60,000 , Europe, 35,000, Australia, 40,000,  the Americas 35,000-15,000; Cavalli-Sforza et  al. 1994:112,154-7). But its organization was obviously lacking and did not satisfy the minimum conditions of world system:  common identity, solidarity, sources of collective action, and a resource base, that would establish at least a  potential for species-wide undertakings. That is why one question for this analysis is to establish the transition from "less advanced" to "advanced", that is from pre-world system to world system, forms of species organization whose formation is still underway.

A 'singular' world system

All this discussion presupposes what we might call the 'singular' conception of world system. Such a conception maintains that the human species has, throughout its existence exhibited, and will continue to exhibit, important regularities and common behavioral patterns, not only at the level of individuals but also at the collective level of common rules and institutions. It stands for the idea that the behavioral uniformities of humanity viewed as an interacting whole are worth knowing about, and the changes in those characteristics, a most important object of study for the social sciences.

There are some interesting parallels here with interdisciplinary debates about the origins of modern humans. On the plural (or polycentric) view, homo sapiens sapiens emerged, in the past several hundred thousand years, separately but by parallel evolution to form distinct races in the world's major regions. The "singular" view, that is supported by contemporary genetic research, as reported by Cavalli-Sforza (1994:p.62 ff), sees to-day's world population as the product of a single expansion of "antomically modern humans" from Africa over the past one hundred thousand years.

The singular conception of world system (as shown e.g. in Frank and Gills 1993) might be contrasted with the 'plural' one, that which proceeds from the existence of a plurality of world systems (as e.g. in Chase-Dunn and Hall, 1991, Wilkinson 1991). These are called 'world' systems mostly not because they extended actually or potentially to the whole of the human species or because they covered the entire planet but because they are deemed to have been self-contained or regarded by their members as 'worlds-in-themselves'. In the plural conception a major question becomes that of system identity, of relations among world systems, and the merger of world systems into "super"-world systems: where do we draw the boundaries, and how do world systems merge into the contemporary, "singular" one.

Our own preference would be to use terms such as "regional" or "local" for systems that may seem to have been self-sufficient, or whose distinctive characteristics appear to confer a special identity, and reserve the term world system to that one whose operations, potentially or actually, are coextensive with humanity. The distinction is not unimportant. It is not merely  an  idiosyncratic  choice  between  "lumpers" and "splitters": between those who see things writ large, and others who see reality, in the first place, only in the microcosm. It is also a choice between the sort of question one deems important: a broad-gauged inquiry into the behavior of humanity, or a detailed accounting of the fates of individual societies each interesting in their own right, that might also, in the aggregate, add up to the story of humanity. This difference is not a new one, and it revives debates that have been current for some time in the study of world history.

For Condorcet, in his pioneering account of human progress, or for Immanuel Kant, in his concept of "universal history", the story of the world was, in the first place, the story of humanity. For those thinkers there was only one (evolving) world system, and one world civilization. Contrast this with influential conceptions of "multiple" (or plural) civilizations viewed, in Arnold Toynbee's (1934:51) words as "the intelligible field" of history conceived as the "comparative study of civilizations". For Toynbee, as for Oswald Spengler, "civilizations" were the societies that had a "greater extension, both in Space and in Time than national states or city states" but none of which embraced "the whole of Mankind" (ib.,p.45). The story of mankind was for them an account of the life cycles of these distinct civilizations, of which he identified more than twenty.

This "plural" perspective, of a number of separate civilizations pursuing essentially independent careers may be contrasted with McNeill's (1963,1991) position that the cultures of mankind have experienced a significant degree of interactions with other cultures at every stage of their history and never more so when great transformations were underway in the world system. For McNeill, the present state of world organization is the consummation of a single continuous process that he recently (1991:xxii) described as "ecumenical".

We find the "unitary" conception potentially more economical than the plural, even though the two are not at all mutually exclusive. Given our interests, we find less useful the Toynbeean concept of a plurality of civilizations and adopt instead a 'singular" or 'unitary' view of the human project as a quest for pushing to its full the potential for species organization. The story of world system development then becomes that of the search for actualization world system potential via learning.


The explicandum: structural change

A process definition of the world system naturally focuses attention upon sequences of change in the social organization of humanity. But which, more specifically, are those changes that need to be explained?

We propose the following four sets of changes in the world system are the proper targets of explanation:

1. Epochs of world system history, -3500 - +2000; the conventional periodization of the story of the human community;  what explains those major watersheds of human development?

2. World system development: how the economic, political, social and cultural structures of the world system have risen, both separately and in tandem with one another;

3. The modern global system and its inception, and in particular the world powers as drivers of economic and political growth;

4. The onset of civilization: ca.-3500, hence also the inception of the world system; what constitutes civilization?

These are, at different levels of analysis, four sets of questions about key aspects of the growth of the world system in the past five thousand years. The first looks upon the world system as a whole. The second distinguishes between the several horizontal structures of the world system, and the third focuses upon a prominent vertical structure of the modern world, the global system. The last concerns human evolution as such. All four pose large questions and they demand solid explanations.

The explanans: evolutionary logic

To answer these large questions about the social organization of the human race we employ an evolutionary explanation. What constitutes an evolutionary explanation in this case? (See also Modelski 1994; Andersen 1994:14).

A social-evolutionary explanation is an explanation of a fact of social life by reference to previous facts as well as to a causal link that may be shown to include:

(1) a mechanism of variety-creation;

(2) a mechanism of cooperation (and segregation);

(3) a mechanism of selection, and

(4) a mechanism of preservation and transmission.

World system processes, at their several levels of analysis, are each an integration of these four mechanisms. As a very rough approximation we might say that the first of these mechanisms is cultural, the second social, the third, political, and the fourth, economic. Since such a synthesis has to be an ordered one, all world system processes have a time-structure that allows for successive optimizations of these mechanisms in a sequence that is a learning sequence (or algorithm), represented in the order in which these mechanisms were presented in the preceding paragraph. World system processes therefore possess the make-up of a four-phase temporal learning experience.

The crucial underlying hypothesis here is that of constant rate of evolutionary change. That is the hypothesis of a "molecular clock" timing genetic mutations over long time periods, and helping to explain the time elapsed in the separation of two species. Cavalli-Sforza and associates (1994:33) use that same postulate to study the history and geography of human genes. They define the rate of evolution as the amount of evolutionary change - measured as the genetic distance between an ancestor and a descendant - divided by the time in which it occurred, and they report to have found that the hypothesis yields good results when used to compare major population changes. A directly analogous procedure has also been employed in linguistic analysis and is known as glottochronology (Swadesh 1971:271) and is used to date the origin of languages by assuming a constant rate of replacement: a "relatively constant rhythm of substitution" in a basic vocabulary, with an average retention rate of some 86 per cent per one thousand years. Results from linguistic work tend to reinforce genetic studies even though the rate of genetic change is, of course, much slower than that of languages.

This leads to the following postulates:

1. World system processes, at all levels, are evolutionary in character;  they are self-similar in that the same explanatory logic applies at each level, implying that the system has a fractal structure. Self-similarity is "symmetry across scale", a "repetition of structure at finer and finer scales" (Gleick 1987:103,100).

2. World system processes undergo change at a constant rate, and have a phased time-structure that integrates the four evolutionary mechanisms of variety-creation, cooperation, selection, and reinforcement. Each period of an evolutionary process consists of the four phases of the learning process.

3. World system processes flourish in conditions conducive to innovation.

4. All world system processes are nested and synchronized (they co-evolve). Nesting means that large-scale processes enfold, and are in turn animated by, smaller scale processes of determinate proportion in conditions of synchronization.

In other words we do not search for a distinct logic for each era or structure of the world system;  "one system" rewquires "one process". We propose one common logic (or algorithm), an evolutionary one, for the explanation of every world system process.

Sources for evolutionary explanation

The classical source of l9th century philosophies of history is Immanuel Kant's "Idea for a Universal History" (1784, 1991). Kant himself was not an evolutionist, but his basic ideas might be thought of as foundational for evolutionary explanations. He raised the question whether it is possible to discover, among free-willed human actions considered on a large scale, "a regular progression", "in accordance with natural laws", in the "history of the entire species", such that it might be recognized as a "steadily advancing but slow development of man's original capacities". He also put forward nine propositions as guidelines for such a history, the fourth of which identifies "antagonisms in society" as the long-run source of a "law-governed social order" and comes close to portraying them as mechanisms of selection. We cannot but take heart in the ninth proposition, that "a philosophical attempt to work out a universal history of the world in accordance with a plan of nature ... must be regarded as possible" and read it as a prescription of a search for a better theory of the world system, though we need to debate in what sense and to what degree such a "plan of nature" might be thought to be "aimed at a perfect civil union of mankind".

Nineteenth century evolutionary thought assumed two main forms. The founders of sociology,  Auguste Comte and Herbert Spencer, advanced bold evolutionary conceptions of the development of humanity, but while aspects of their conceptualizations, of a phased advance toward industrial society, remain influential to this day, they are on the whole regarded as dated. Marxist thought developed along similar lines. This broad "evolutionist" strand of thought might be contrasted with the "selectionist" approach of Charles Darwin, whose revolutionary contribution was the identification of natural selection, and variation, as mechanisms of species development. Darwin also launched the idea of a "tree of life", the common origin of life on earth, and in effect also launched a macro-history of biology; but he avoided any grand claims to explaining patterns of human social evolution.

Social evolutionary thought experienced a revival in mid-20th century, just as Darwinian biology was reinvigorated through the "modern synthesis". In economics, the work of Joseph Schumpeter, among others, is now recognized as "evolutionary", and viewed as an important alternative to neo-classical analysis. In sociology, Talcott Parsons was, in his later work, a significant contributor to social evolutionary theory. More recent social thought has been less hospitable to such theorizing. Anthony Giddens (1984:243,236-9), for example, compounding evolutionary theory with historical materialism, has argued that it is necessary to deconstruct them both. "In explaining social change, no single and sovereign mechanism can be specified. There are no keys that will unlock the mysteries of human social development ..." "Human history does not have an evolutionary shape"; history is not a 'world-growth story' because the relatively short period since the emergence of civilization in Mesopotamia "is not marked by the continuing ascent of civilization; it conforms more to Toynbee's picture of the rise and fall of civilizations".

We disagree with this position, and attempt a synthesis of "evolutionism" with "selectionism". That is, we aim to explain large-scale social change, but seek to do it by carefully tracing the processes and the mechanisms that propel such change, and " selection" is the chief one, though not the only of these mechanisms, as just noted.

In social theory, we need to contrast the evolutionary explanation  with rational choice, and with  functionalism. Rational choice (Elster 1989), whose paradigm is neo-classical economic analysis, is an elaboration of what Max Weber called the ends-means schema. That schema takes opportunities (and constraints), as well as preferences (or interests), as given and generates from them a stream of intended outcomes. By contrast, selectionist and evolutionary models do not depend upon intentions;  they focus on actual outcomes, and they make changes in constraints and interests as part of the model. Design, the ideal product of rational choice, is not part of selection that plays upon trial-and- error. Speed of response is the glory of rational choice; evolutionary change is the tortoise that moves slowly but surely over the long haul.

Selectionist models therefore seem preferable for studying evolutionary processes and macro-level phenomena such as world system change. Nor are they to be confused with functionalism. Classical functionalism asked: what maintains social structures? The answer was, a practice that responds to a (postulated) social need. Critics (such as Little 1991;101-20) are right in arguing that this implies an excessively optimistic, "Panglossian" meta-theory, that "societies will produce practices that satisfy their long-term needs". Evolutionary explanations, on the other hand, seek to explain not persistence but social change and the processes that transform social structures.


A periodization of world history

Schemas of historical periodization are accepted ways of identifying, and describing, long-range social  change. William McNeill's (1963) periodization of world history (and shown in first column of Table 1) might be regarded as a standard specification of changes in the world system in the past 5000 years or so (but see also comments in 1991:xvii-xix). That periodization is based on the factor of "dominance", and relies therefore, in the first place, on changes in large-scale political organization. Hence it might illuminate only one facet of the world system process, but there is no reason to suppose that it is unimportant or that it is not intimately related to the other principal components of the world system. Indeed, there are grounds for thinking of political periodicity as a kind of "clock", timing the entire social system. In any event, these periods conform quite comfortably with the headings under which these matters are conventionally arranged: those of ancient, classical, and modern history.


On McNeill's account, the political organization of the world system has now passed through three stages. In the first, starting well before -3000, the Middle East was the center of world development. In the second, no one region of the world occupied a similarly striking position, and the situation was, on the contrary one of "cultural balance" in which "each of the four major civilizations developed more or less freely along its own lines" (1963:253). The third stage might be thought of as a return to dominance, and this time, "Western dominance". The long term vision of the future, hence also possibly of a fourth phase, is indicated, by a reference in the book's closing pages, to the "establishment of a world-wide cosmopolitanism" (a Kantian term) that "would enjoy vastly greater stability" (ibid.:806-7).

Shifts in the patterns of dominance might suggest no more than world-wide reshufflings of power structures, but they also serve as useful markers of world time. If we combine our phases with demographic data in Table 2, we observe over the entire period a tremendous growth in the world population since before the (postulated) inception of the world system. To each of the conventional stages, with population measured roughly at mid-point, corresponds a new order of demographic magnitude. Throughout "history", that expanding population shows a fairly even distribution in space, with the major regions of Asia invariably accounting for more than one half of the world total. What we have here is a vast expansion in the membership of the human species as a whole, hence a systemic process, one that must have been associated with significant structural changes, in all dimensions of social organization, one of which was urbanization.


Explaining the phase movement

What we have here is a process with a strong phase-structure, both political and social (demographic), that also is suggestively cumulative and in a sense progressive. How do we explain the phasing of this process?

We propose an evolutionary explanation. We argue that the process is one of the emergence of the world system. Or else we say that the process is one of launching of the world system as a major social innovation. The standard periodization reflects the political phasing of that process, and the cumulative demography reflects successively more effective conditions of world organization. Each phase of that process, broadly corresponding to the eras of the conventional periodization, is marked also by the optimization of one of the four major evolutionary mechanisms.

Our model therefore proposes that the evolution of the world system passes through four phases: those of culture-base (laying the basis for variety-generation), community-building (building the foundations for large-scale cooperation); collective organization (selection of forms of world organization), and consolidation (reinforcement and replication).  These would represent successive optimizations of evolutionary mechanisms in relation to the world system process. They might also be seen as phases of the learning process that Talcott Parsons and his associates described in 1950 as the LIGA sequence (Modelski 1987:104ff), a sequence that constitutes a learning program. If structural change, that is social learning viewed as problem-solving, is to occur, these phases must be passed in the sequence just presented, in that the completion of one phase depends of conditions created by the preceding phase, and becomes a necessary condition for the phase that follows. Each of the phases represents the principal theme of the world social universe in major epochs of its functioning; they reflect major social priorities but need not imply total neglect of other domains of social organization.

The first phase (in Table 1), labeled "culture-base" might be understood as generating the variety for building the world system, and does so by drawing upon the resources developed in the preceding era (in this case, the agricultural revolution). That variety arises in the context of city-building and gradually spreads, in a system of interconnecting networks in intercontinental proportions: cities being by definition cultural constructions that are oriented to, and closely linked with, other cities, coming to form the base of the world system.  The essential feature, and the key innovation of the culture base becomes writing. Writing organizes social life both to the past and to the future; it lends it continuity and makes systematic structural changes possible. It leads to the growth of schools, hence education, and professional classes (e.g. scribes, and teachers);  it is centered on temples, and helps, as do cit ies, in differentiating culture from the social system. Writing means the start of systematic learning, and of science (as in astronomy, calendars), makes irrigation possible, and is essential in disseminating the elements of bureaucracy and organization.

Proceeding from the culture-base thus formulated, the next major phase of world system formation goes on to community- building on a scale extending beyond tribe and city. This phase innovates the structures of wider cooperation implicit in the world system, because potentially such cooperation must extend to all humanity. We propose that in this, second phase of the world system process such potential assumes the form of universa l religions. Religion, in turn, forms the basis for solidarity and cooperation, enhances communication and education, large-scale political organization, and long-distance trade. Each in their own way, the great religions are in turn forms of differentiating populations and building large regional ensembles.

Given a set of major communities, the stage is ready for organizational selection. Competitive pressure in the world system selects the organizational forms best attuned to the emerging complexities of the world system. The collective management of human affairs becomes an operative problem, both at national and global levels. Such collective organization finally paves the way for adaptation, a stabilization comprising an adaptive adjustment to the environment, yet preparing the stage for yet other evolutionary developments.


Testing the model

How does our model square with the conventional periodization of the history of humanity? To do this, let us compare the columns in Table 1, where the two to the left show the major divisions of world history and that on the right suggests ways of conceptualizing them. In both instances the dating starts at about -3500, a round figure for the start of the Sumerian era, but we do need to observe some differences between the two presentations. The left column consists of periods of unequal length that nevertheless average out to a little over 2000 years; the right-hand column world system phases are postulated to be of roughly uniform length, just over 2000 years. Unless shown to be otherwise,  the assumption of constant rate of change and phase uniformity holds greater initial plausibility because of requirements of synchronization. The (four-phased) world system process would then extend over 8000 years.

Can the era of "Middle Eastern dominance" be correctly described as a phase of "culture-base", as predicted by the model? We observe, first of all, that the Middle East was not dominant in the sense that it might have "controlled" say, China, or Europe, but because it was the location of the major innovations of that period. That is where the first systems of writing appeared, thus effecting the transition from oral to written culture, a major breakthrough in social organization, setting in motion the differentiation of the cultural system from society. This was also the area where cities first emerged, and cities were the first great human artifacts that manifested human cultural achievement, but also laid the foundation for an entirely new form of social organization, becoming the core of civilization.  Both stimulated new departures in society, speeded up technological innovation, as in astronomy, civil engineering, and irrigation, laying down the groundwork of conditions in the absence of which a world system could not be constructed and on the basis of which the great religions rose in the next era. The end of the period, "a major turning point in the history of civilization" (McNeill 1963:249) brought "the democratization of learning implicit in simplified scripts", making possible the spread of literacy, hence access to information, among wider and wider segments of society. It also saw the spread of cities to other regions of the world.

To reinforce what might be an unfamiliar argument about the emergence of a "culture-base" of the world system, we present, in Table 3, for the entire span of the world system to-date, a summary of the evolution of external means of transmitting information. Such technologies are the essential preconditions to the creation of variety, hence a sine qua non of evolution, and the table reveals that the majority of these crucial innovations may be attributed to the first phase of the world system, and a major part of it, to Sumer. Not until the Information Age of contemporary experience has the world known a similar burst of creativity in this domain.


At the start of the second major era, that of Eurasian cultural balance, "there existed four distinct regions of high culture in Eurasia", and "two thousand years later the physiognomy of Eurasia was recognizably the same" (McNeill 1963:249) , and we might add, persists to this day. Balance replaced dominance, establishing a condition not just of relative autonomy but also, more importantly, one in which each major world region contributed its share to world development, and shared in its evolution. What was the nature of that contribution?

Our model proposes that in this "classic" era, the major priority, and critical innovations, lay not in erecting great empires, but in "community-building". This was, indeed, the era of world religions. The Eastern Chou era of Chinese history brought forth Confucianism. The ideas of Confucius "catalyzed the institutional and intellectual definition of Chinese civilization" (McNeill 1963:232), and moulded the cadres of its scholar-officials. The teachings of Buddha came to be institutionalized in the Mauryan context in the Indian sub-contin ent, and then spread to influence West and Southeast Asia, and East Asia as well. Buddhism was organized around the practice of monastic communities. Christianity formed in the Mediterranean under Roman rule, and then shattered it. The Ummayad and Abbasid Caliphates became the framework for Islam, resolving the issue of "how the community of the faithful should be led and by what principles it should be governed" (ib.:429). Accounting for "much of the institutional pattern" that gave Islam its strength was "the strategic position of the mercantile class" (Hodgson 1993:107).

We observe that all four of these cases have in common the creation of a new basis for a potentially universal community;  none succeeded to a full degree but each in its own way served to lay the foundations for a more inclusive world organization, but each in turn contributed their own important aspects to the building of community. We observe though a contrast with Karl Jaspers' concept of an "axial age" (-800 - -200), the age of he regards as that of Confucius, Buddha, and Socrates, an epoch at the center of world history during which all fundamental creations of current civilization had taken shape almost simultaneously across Eurasia. Our own "learning" conception is conceptually sequential.

If the classical era was, in its basic thrust, Eurasian, then the modern era might more appropriately be labeled "global", and we might wish to suspend judgment on the question whether this should be called the era of "Western dominance". If, as William McNeill (1983) has more recently urged, we see the modern world system as beginning to take-off as early as one thousand years ago, in Sung China,, then its complexion must a mixed one, with the Chinese Renaissance being followed by the Italian, and Western Europe only taking a leading position well into that process, after 1500. Maybe it is too early to give a final definition of that era whose likely reach might extend for some more centuries.

But we might be entitled to assert that, propelled by a powerful "organizational revolution", prominent forms of collective action, not old-fashioned empires, but nation-states, corporate business entities, armies and navies, universities, now dominate the social landscape that also includes a growing network of global institutions. That is how we would define the most striking social innovations of the modern age, and it is these innovations that have given substance to the term "world system". We can see the four phases of that process as preparatory and cultural (the Renaissance), that of the emergence of a nucleus of the world system in Western Europe, and currently the phase of world organization, yet to be followed by stabilization.

We have now traced world system processes through five millennia but we also observe that the substance of the world system did not become apparent until the most recent centuries. That is so because we are attempting to uncover a process by which the world system evolves, and that evolution always starts slowly at first and reaches a point of crystallization (via punctuation, as in punctuated equilibrium) only some distance along the way, usually in the third, the selection, stage of the process, that is at mid-point of the learning process. For the world system, that would be the stage of collective organization that has been under way for the past millennium, which is the time when the fact of world organization first started to become a reality.

Where all this might take us is a matter for informed speculation but the concept of "cosmopolitanism" is not incompatible with the "post-modern stabilization/adaptation" that is predicted by our model for the fourth phase of the world system process.


What have we learnt so far about world system evolution? That a gross ordering scheme in evolutionary terms is at least conceivable and that a gross characterization of the epochs of world history in terms  of (culturally-conceived) social priorities, and the major innovations responding to these priorities, is not inherently implausible. Such a model cannot be rejected as glaringly at variance with the conventional scheme of things, and is in fact better than could be expected from an exceedingly macro-model. Equally clear, we must also make this ordering more convincing by reducing the extended time-span between cause and effect, and by introducing additional mechanisms of less grandiose time-dimensions.

We have treated the conventional periodization as applying across the board to the world system process. But we noticed too that the basis of such periodizations is in the first place expressed along one dimension, the political or the geo-political one, because it invites us to view world system development through the lens of such concepts as Middle Eastern dominance, or Eurasian balance (that is, absence of dominance). Clearly, political evolution constitutes one aspects of the world system process, meaningfully related to other like processes. How might political world system evolution be explained, and how might such political process be related to, shall we say, the main currents of economic change in the world system?

We recall that we conceive the world system as composed (along the horizontal dimension) of a set of four self-similar, and  nested, structures (enduring forms of networks  of  interactions): economic,  political, social and  cultural.  We  call these  structures  self-similar  because each is subject  to  an evolutionary  process of the same logical make-up, but the process proceeds at different time-scales. That is, the rate at which the economy changes is faster than developments in structural politics, etc. Because the scales of these processes differ, some might be thought of as nesting within others;  that is e.g. economic changes may be thought of as occurring within a larger political framework. Nesting calls for synchronization, and that is why the time-scales of the several evolutionary processes must stand in a determinate relationship to each other. The whole forms a spectrum of processes of interlocking periodicities. We hypothesize the following relationships among these processes:



In other words, we propose that the constituent processes of the world system interlock in a determinate manner. While all these process undergo change at a constant rate, the periods of their processes differ in a determinate ratio. By that we mean that four periods of the world economy process are equal to two periods of the active zone process, and one period of center-hinterland process.  The relationship, at the world level, is thus regulated by the relative scale of these various event sequences. That relationship, in turn, reflects what Talcott Parsons (1966:9,24,113) called the "cybernetic hierarchy" according to which "the longer the time perspective, and the broader the system involved, the greater is the relative importance of higher, rather than lower, factors, in the control hierarchy". In such terms, the overall process of world system evolution that we reviewed in the preceding section might be analyzed (or refracted) into four distinct processes that stand to each other in a relationship of 1:2:4:8, and each of which is composed of four phases, reflecting the operation of basic evolutionary mechanisms.

World system process We hypothesize that this is the process that gives overall shape to the world system,  programs it, orders its priorities, and times the major phases we have just discussed.  It takes its cue from the world information networks, and is at bottom a cultural process that gives a distinct texture to major epochs of world culture that we have already observed in Table 1.

Center-hinterland process The evolution of a human community and the growth of human solidarity is not a process of linear growth but one of persistent tension between the pressures to innovate that are the consequences of evolutionary developments and a necessary outcome of learning, and the demands for equality that is the operating requirement of every community. Innovations produce concentrations of metropolitan power, and peaks of prestige systems, often centered on opulent cities and powerful empires; forming in opposition to them are the hinterlands, or the margins of "civilized society" that from time to time organized themselves to effect a systemic leveling (or "dependency reversal"). It is hypothesized that major phases of center concentration, a millennium in length, alternate with equally significant intervals of hinterland assertiveness.

We borrow this pair of terms "center-hinterland" from A.G. Frank's recent (1990) studies. It parallels the conceptual pair of "core-periphery" but it needs to be distinguished from it because the latter is based upon a differential division of labor; the former is that of a social relationship that might be grounded also in differential distributions of political power, social prestige, and claims to innovation.

Active zone process An active zone is the spatial locus of innovation in the world system. Social and cultural evolution proceeds by means of innovation and its diffusion, and it flourishes in conditions that favor the generation of variety and evolutionary processes in general. The political seedbeds of such variety are not powerful empires that tend to attract the eye of historians but zones of autonomous entities, such as state systems, and intermediate political networks, and more broadly regimes and domains in which individuals and communities enjoy freedom and autonomy that favor creativity.

Thus conceived, active zones might be seen to serve as the capital zones of the world system, as long as they keep generating the innovations that respond to world problems. The active zone process is the political process that in each period of 2000 years focuses upon a broad geopolitical zone  but that also in each of its phases (of about one half millennium) moves along spatially to a new region of the world system. Standard eras of world history might be seen also as periods of the active zone process.

Production/commerce A hypothesized world economy process defines changes in the major modes of the organization of production and exchange in respect of agriculture, mining and industry. Periods of productive development, and surges of new technologies (such as bronze, or iron) alternate with others that expand networks of interchange, pioneer new trade routes, and generally disperse such innovations. Such changes animate, and are in turn controlled by, the active zone process.

Model presented

Table 4 presents this model for visual inspection, to show how these processes coevolve. It spells out, in the third column the sequence of active zones that adds detail to our earlier discussion of geopolitical regions, and adduces other information that put some flesh on the bare bones of this structural argument.

The first column of Table 4, world system process, repeats the phases shown in Table 1, and we have already reviewed these, each also defining a major theme of cultural development. In turn, in column 2, we show each of the epochs of the world system comprising two phases of the center-hinterland process. We know that the core-building that produced the flowering of Mesopotamia, of Egypt, and of the Indus Valley, was ru dely interrupted by a wave of "high barbarism". "Beginning about 1700 BC, a wave of barbarian  invasions initiated far reaching changes in the political and cultural map of the Middle East" (McNeill 1963:110). Several groups of invaders, having mastered the techniques of chariot warfare, collaborated in overrunning the rising centers of ancient civilization in the Middle East and the upshot was the formation, in that region, of what McNeill calls a "great society", as well as the projection of strong influences on the formation of civilization in other parts of Eurasia. In other words, a pattern of core building was followed by a period of leveling.

The dispersion affected by the barbarian invasions then served to consolidate the core of four civilizations, East Asian, Indian, Mideastern, and European, that came to constitute McNeill's "balance of Eurasia". It is within that balance that each of these contributed to the major process of community-building that was discussed in the preceding section. But after the year 200 the structures thus erected once again came under the pressure of a "barbarian breakthrough" (McNeill 1963:385 ff). The movements of Germanic tribes that broke up the Roman empire were part of the same great migration as the barbarian occupation of North China, and the Ephalite invasions of India. The eruption of the tribes of Arabia upon the Mediterranean world after 632 completed what appeared to be another sustained process of systemic leveling.

In the early modern era it appeared for a moment as though under Mongol rule, China, might become the center of the world system. But the attempts at world empire collapsed, and the active zone moved to the Meditarranean. We are familiar with the thought that after 1500 the center came to reside in West Europe, in a manner such that various parts of the world system became increasingly dependent upon it, in colonial and semi-colonial situations.


Our analysis would predict that, once again, this extensive period of systemic concentration might be due for a reversal: the world system might have entered, after 1850, onto a movement of systematic leveling, though hopefully at a higher level of organization. This leveling might be taking the form of democratization, in which an initially small core of democratic societies (about 10 per cent of the world population at the end of the 19th century) might be gradually bringing  into the fold of a future democratic community a larger and larger portion of the world's peoples (approaching 50 per cent of a much larger population at the turn of the 21st century).

How might this be so? On this analysis, the center-hinterland process is now in its second period (of 4000 years each). The first, labeled here "Rough World", was in a sense unsurprising, for in the course of it the splendor of civilization was regularly, albeit at long intervals, balanced by  the excesses of those who attacked it in order to share in it, and sometimes to destroy it. While this was indeed a rough world, maybe there was also in it an element of rough justice.

Can the rough edges be take off the world system? Robert Axelrod (1984) has argued that even in a "nasty world", "nice strategies" can arise as mutations of established operating procedures, and in certain conditions, namely those of clustering, might not just survive but also prosper. Let us therefore entertain the proposition that the second period of the center-hinterland process might be one experiencing a move toward a "nicer world".

At first, we would, once again, expect a stage of reconcentration, powered by prodigious innovation in forms of global organization, giving rise to much dependency. But the same process would also be responsible for setting off mutant forms, in Sung China, or in Italy, launching experiments, reformist, republican, and liberal that build up potential for social and political development. It is from those mutant forms that cooperative arrangements could arise and lift the raw conflict among center and hinterland to a higher level of performance. The diffusion of democracy since the 19th century across the world, to i.a. Japan, India, Eastern Europe, and parts of South America, is beginning to create conditions in which demands for greater equality might find expression in forms that are "nicer".

The sequence of active zones (in column 3 of Table 4) has been neither arbitrary nor unsystematic. The progression described by that sequence has been along zones of spatial contiguity, and has successively lent priority to cultural, social, political, and economic factors. Thus in Confucianism, for instance emphasis is placed on scholarship and learning;  in Buddhism, on the development of the monastic community;  in Christianity, on church organizational factors, and in Islam, on the evolution of long-range communications based on pilgrimages and trade-routs facilitated by that community.

The active zone process can be documented with the help of data on world urban populations, cities in active zones being the seedbeds of major innovations. Recent research (Bosworth 1995:198ff) shows that the process appears to capture "those regions whose population growth outpaced those of the rest of the world, with each active zone building upon the foundations of its forerunner". For each of the zones identified in Column 3 after -1000, that is for all those for which usable data are available, the population of the top-25 cities in that active zone exceeded that of every other region in the relevant time period.

As expected, the active zone is shown to have been, in most cases, an arena occupied by autonomous political systems, from the city states of Mesopotamia, to the interstate systems of the Middle East, the Eastern Chou, and India. Rome splintered not long after its emperor embraced Christianity; and the Islamic Caliphates were noted for the flexibility of their political organization. The city-states of Ancient Greece might appear as a notable omission but it was in their shaping of the Hellenized society of the Mediterranean created by Rome and inherited by Christianity that Greek culture found its enduring place.

At about 1000, it appeared as though Sung China, then the most conspicuous member of the East Asian region might take the lead in the world system, such that this could be regarded as "The Era of Chinese Predominance" (McNeill 1982:24 ff).  But the Sung first lost the North, and then fell, in the South, before the onslaught of the Mongols. It is the Mongols' design for world empire at the center of Eurasian land mass and the dominance of their huge cavalry armies that defined this age as one of " Eurasian transition", from East Asia to Europe.  The Mongol's project extended from China over most of Eurasia, but it never completely materialized, nor did that of Timur, and imposing though both were, they soon collapsed under their own weight just as the last European attempts at medieval empire (those of Charles of Anjou) crumbled even before getting properly underway. The republican regimes of Genoa, and then Venice, were the initial beneficiaries of that transition, took up the challenge and became the springboards from which West European power was projected world wide after 1500.

The fourth column of Table 4 suggests the outlines of the evolution of the world economy (see also Modelski and Thompson 1995:Ch.8). The world economy process begins with Bronze as

a basic new technology, with implications for weapons production and tool-making in particular. That technology favored urbanization, helped to raise levels of production, and created conditions favoring increased trade. Then the Bronze age is rounded off with the emergence, in the Fertile Crescent, after about -1500, of a "civilized core area" (McNeill 1963:113) serving i.a. as the framework of economic organization.

Between -1200 and -1000 in the Middle East and in Europe (though in China not until -600), iron working begins to assume general importance, replacing bronze as the primary metal for tools and weapons. The "closure of the Eurasian ecumene" in turn provides the opportunity for a notable expansion of long-term trade, chiefly by land but also by sea, with the Silk Roads assuming a key role in that process in the fourth period in particular.

The modern age is clearly notable for the establishment of more flexible and productive "market economies", especially in the sense of an increasing differentiation between economy and polity, the consolidation of the economy as a potentially self-organizing system, and the increased role of autonomous, and increasingly corporate, business organizations. The groundwork for that development was laid over the past millennium, and more recently, say after 1850, conditions began to ripen for the creation of a world market, as the framework of exchange in a now strikingly productive world economy.