To paraphrase Sternman, what is the relative importance of intensive versus extensive forces in the birth and death of societies? Language and religion are two of the defining attributes of a society. Both are intensive -- they apply to each member of the society. Militarily, economically, and politically, the society may be independent, or it may be under another society's control. These attributes are extensive, emergent properties of the society as a whole and the area it occupies. Historically, some societies have maintained distinct identities while under another's control, while others have lost their identities in the same circumstances. Why has China typically been unitary? Why has western Europe typically been fragmented? Why have the southern Balkans and Anatolia been alternatingly unitary and fragmented? These are not well understood issues for the historian, whose model for understanding is typically narrative and prosaic. But cast into the terms of System Dynamics, these issues can be comprehensively articulated and tested. This paper will explore the underlying structures of these historical dynamics and describe the reference modes in the dynamics of societies in Anatolia and the southern Balkans over the last 2000 years.

In my 1995 paper, I referred to the cohesion of a civilization as being a key state variable in determining its extent and duration. In the current paper, I elaborate further: social cohesion is the confidence of a population in its social paradigm. A society has members, who produce and consume goods and occupy land. The people have a characteristic language and religion. In France and Italy, the current patterns of language and religion -- Latin Christianity -- were set by 400 AD. In Spain and Portugal, that same pattern was changed in the 8th century, then changed back by the 15th century. In South Asia, the patterns in Tamil Nadu - Tamil Hinduism -- were set by the 6th century. In the Punjab, by contrast, there have been several changes since then. And at the crossroads of Asia and Europe, the changes have been complicated:

year Anatolia SE Balkans SW Balkans
300 BC Greek pagan (G) Greek pagan (G) Greek pagan (G)
400 AD Greek Christian (G) Greek Christian (G) Greek Christian (G)
700 AD Greek Christian (G) Bulgarian Pagan (G) Greek Christian (G)
900 AD Greek Christian (G) Bulgarian Christian (B) Greek Christian (G)
1200 AD Turkish Moslem (T) Bulgarian Christian (G) Greek Christian (G)
1500 AD Turkish Moslem (T) Bulgarian Christian (T) Greek Christian (T)
1900 AD Turkish Moslem (T) Bulgarian Christian (B) Greek Christian (G)

Table 1. (G) = Greek rule, (T) = Turkish rule, and (B) = Bulgarian rule.

Greece has been Greek Christian since the 4th century. Bulgaria has been Bulgarian Christian since the 9th century. Why did Turkey become Turkish after 300 years of Turkish rule, while Greece and Bulgaria did not?

Consider people in a society as members of a cultural paradigm. While political, military, and (to a lesser extent) economic affairs are extensive and can be regulated from without, religion and language are intensive and not so easily prescribed. Belief in the old society has to be eroded before a new one can take root, before people are willing to shift allegiance to it. The conquest of Greece and Bulgaria by the Ottoman Turks in the 14th and 15th centuries was a relatively quick political and military expansion by a society nearing its peak. The existing religious and linguistic loyalties of the Bulgarians and Greeks were not tested, and no shift took place. By contrast, after the 1071 AD defeat of the Byzantine Greeks by the Seljuk Turks at Malazgirt (Manzikert), a relatively quick occupation of interior Anatolia was followed by three centuries of back-and-forth conflict between a variety of small states: Turkish, Greek, Armenian, and Frankish; Christian and Islamic. They reduced the confidence of the people in Anatolia, so that when the strong and confident Ottoman Turks established themselves in the 14th and 15th centuries, Anatolia became Turkish Islamic.

There are 'puzzles' that a cultural paradigm solves, but stress can disrupt the patterns of an existing paradigm. A deficiency in the ability of one paradigm to provide by comparison to another will cause a migration between paradigms.

Key issues:

If a local paradigm weakens, the options are: Anatolia and the southern Balkans had uniform, cohesive, linguistic and religious identities in the period 1st - 5th centuries AD. The people were speaking Greek and observing classical Greek religions, then shifting together to Christian beliefs. In Anatolia after 1071, the extensive aspects of society -- political, military, and economic -- were in flux for three centuries, but eventually became Turkish. The intensive parts of society -- religious and linguistic -- also became Turkish. A simple model will suffice to explain this mode: intensive aspects follows extensive ones with a delay.

The SW Balkans were Greek for over 2000 years. Their external social aspects became Turkish in the 15th century. But Greek Orthodoxy and the Greek language continued in common use. In the 19th century, the extensive aspects of society again became Greek. A simple model would suffice to explain this mode: intensive aspects are unchanged by extensive aspects. To reconcile it with the previous example, the time constant for change had lengthened since 1071.

The SE Balkans were Greek for several hundred years, then pagan Slavic in the 6th century. They became Bulgarian in the 7th century. They adopted a Greek religion in the 9th century, were ruled by the Greeks in the 11th and 12th centuries, independent in the 13th and 14th centuries, ruled by the Turks from the 15th to 19th centuries, and independent again in the 1870s. A simple model will not explain this mode.

For each area, consider a trio of state variables -- one for each paradigm, Turkish, Greek, and Bulgarian -- that represents the internal cohesion of a society, as manifested in language and religion. Consider a second trio of state variables for that area to reflect the extensive attributes of military, political, and economic control potential held by Greeks, Bulgars, or Turks. Then the strength of each paradigm within the society will reflect the percentage of adherents within the area, and the corresponding state variables will always add to 100%. Paradigmatic strength will be affected both by extensive pressures within the area as well as by the influence of paradigms from surrounding areas. It reflects both the number of adherents as well as the strength of each individual's affiliation. For instance, a bilingual agnostic would be less strongly tied to the Greek paradigm than a monolingual devoutly Greek Orthodox person. The strength of the Greek paradigm in the SW Balkans will be increased by the strength of the Greek paradigm in Anatolia and the SW Balkans, as well as by extensive Greek strength in the SW Balkans. It will be decreased by the strength of the Turkish and Bulgarian paradigms in the SW Balkans.

In the case of the SE Balkans, there was a depopulation in the 5th - 7th centuries as economic exactions from Constantinople and military conflicts reduced productivity and loyalties as well as population. There was a corresponding period in 11th - 13th century Anatolia. But whereas in Anatolia the new paradigm included Islam, which could withstand comparison to and competition with Christianity, the new paradigm in the SE Balkans compared adversely to the native Bulgarian beliefs, and within two centuries Christianity was reestablished.

More generally, depopulation is not required to effect a cultural paradigm shift. But a disparity between actual and potential population greatly facilitates it, whether caused by depopulation or not. The advent of an agricultural population in a nomadic area, or of an industrial society into an agricultural area, can have the same effect.

The historical pattern of societies is complex and depends on the past as well as the present. An understanding of that pattern requires an understanding of both their intensive and extensive aspects as well as the systematic ways they relate in time and space. A reevaluation of humanity's past in a systematic context can help the understanding of our present and our ability to control our future.


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