About seven years ago I wrote a piece about the mechanism that creates the saeculum. There are a couple of missing figures, but they aren’t necessary to follow the argument, they both show bell-curve distributions of ages or birth dates for those involved in leadership. I plan to use some of the ideas in this mechanism in another thread about the medieval saeculum.


I summarize piece here, for more information refer to the linked document.

3.1 Generations creating history: the constellation model:

1. The length of a generation (L) is equal to the length of a phase of life.
2. Each adult phase of life is characterized by a specific role.
   
   1. Rising adulthood: coming of age (performed at an average age of A_C)
   2. Mature adulthood: leadership (performed at an average age of A_L)
   3. Elderhood: stewardship (performed at an average age of A_S)
   
   
3. A generation occupies a phase of life when a plurality of those performing the characteristic role are from that generation.
   
   1. A generation enters a phase of life when its first cohort reaches the characteristic age
   
   
4. A_C = L; A_L = 2L; A_S = 3L

Section 3.2: How generations create history
Each generation behaves in a characteristic style according to its archetype and phase of life. The sum of these three parallel generation behaviors color a period in a particular kind of turning. This combination of archetypes and phase of life roles is called the generational constellation. Thus, the constellation creates history.

Section 3.3: How generations are created
Strauss and Howe posit that generations are created by the impact of eventful history on the occupants of the different phases of life:

Now suppose a decisive event say, a major war or revolution suddenly hits the society. Clearly, the event will affect each age group differently according to its central role. In the case of a major war, we can easily imagine youths encouraged and willing to keep out of the way (dependence), rising adults to arm and meet the enemy (activity), midlifers to organize the troops (leadership) and elders to offer wisdom and perspective (stewardship). We can also imagine how most people will emerge from the trauma with their personalities permanently reshaped in conformance with the role they played (or were expected to play but didn't). The decisive event, therefore creates four distinct cohort-groups--each about twenty-two years in length and each possessing a special collective personality that will later distinguish it from its age-bracket neighbors as it ages in place.

A problem emerges when the generation-forming decisive event occurs over a period of time. Suppose the generation-causing period runs for 20 years, from the beginning of year 88 to the end of year 107. In this case how do we identify those who "occupy a phase of life" during the event? At the start of the event people born over 44-65 will occupy the rising adult phase of life. At the end the event people born over 42-63 will occupy the mature adult phase of life. Those born between 44 and 63 will have been in two phases of life during the event and so will be imprinted into which generation?

Another approach would be to assume that events create a generation by acting on people performing a single key phase of life role like coming of age. In this case there is no ambiguity, those at the right age during the event get formed into a single generation.

Strauss and Howe identify coming of age as a particularly important role in the creation of a generation:

Practically every society recognizes a discrete coming of age moment (or "rite of passage") separating the dependence of youth from the independence of adulthood. This moment is critical in creating generations; and sharp contrast between the experience of youths and rising adults may fix important differences in peer personality that last a lifetime.

If coming of age is considered to occur over a fairly short span of ages, then the size of a generation will depend on the length of the event. For example, suppose most people come of age within five years of A_C. An event would create a coming of age "generation" born between A_C + 5 years before the beginning of the event and A_C - 5 years before the end of the event. The generation created would be ten years longer than the event. If the events are social moments, whose length runs from 8 to 22 years (Table 1), then the length of generations created in this way would be 18-32 years long.

This sort of a mechanism provides a plausible way to create generations of appropriate length, but it doesn't make use of the phase of life concept. As seen earlier, the constellation model necessarily calls for generation length to be equal to phase of life length. This mechanism also only produces two kinds of generations, "event generations" and those born in between. Strauss and Howe call the former dominant and the latter recessive generations.

Strauss and Howe implicitly identify a cycle of parental nurture in their discussion of their cycle. Nurture is most protective during Crises and least protective during Awakenings. Since parental nurture directly impacts children, this nurture cycle can act to shape people occupying another phase of life (youth) during social moments. Thus, in a social moment, those coming of age are not the only ones "imprinted" into a dominant generation. It is also those who have not yet come of age that develop a generational sense apart from those who did come of age in the social moment. These individuals come of age in the period between social moments and are members of recessive generations.

I develop this idea further, and make the following observation:

Although not explicitly stated, the nurture mechanism outlined in Table 10 contains a built-in assumption about the length of a generation. It is assumed that each generation parents the next. The Adaptive children of the crisis, who received an overly strict upbringing from their disciplined Civic parents, themselves provide a more relaxed upbringing for their own children, which sets the stage for their becoming Idealists in the next social moment. Unless most of the Idealist's have Civic grandparents, they wouldn't get the right type of nurture and so wouldn't be primed to become Idealists. The cycle would fall apart. It is necessary that phase of life generations be about the same length as biological generations. That is, L must be around 25-30 years in length. Table 6 shows six saecula between 1204 and 1844 with an average turning/generation length (L) of 27 years. The two saecula after 1844 show lengths about one-third shorter. Thus, for the period before 1844, the mechanism in Tables 9 and 10 can work.

I discuss Kurt Horner’s ideas on what a 27 year generation/phase of life system would look like.

With this a self-consistent model emerges with L = 26. A value of L = 26 projects a value of 78 for A_S. It is unlikely that any role was played in early modern times by people this old. Dropping the elder component of the generational constellation eliminates one of the three parallel forces producing turnings. The new requirement that generations be created at coming of age eliminates a pre-existing generational character amongst rising adults that can shape history. A generation cannot both be imprinted by history and at the same time create that history. This precludes a major role to be played by those coming of age in the creation of history. This leaves only a single generation in the constellation as the actor on history.

Using a single generation also requires a very strong tendency towards the archetype, which simple observation (see lots of threads here) reveals is simply not the case. Furthermore, with only one generation causing history, any perturbation that disrupts the cycle would throw the mechanism into disarray from which it could not recovered, ending the cycle. As a solution to these problems I proposed an independent supporting cycle that works in concert with the generational constellation, keeping it on track. I call this the social distress cycle. Social distress creates the “sparks” that can ignite turning changes making it easier for the governing generation to produce history. If social distress approximately follows a cycle that is a sub-harmonic of the saeculum, then a saeculum of relatively constant length can be maintained indefinitely. In later sections I propose mechanisms for this distress cycle and attempt to relate it to the saeculum.

I have updated my saeculum models because I have found a suitable free web-hosting site. I have three papers. The first Cycles in American history contains a review of long cycles:

Economic: long cycle in the stock market, capitalist economy (Kondratieffs), and in the agrarian economy (Kuznets or panic cycle)
Social: the Strauss and Howe saeculum
Political: the Schlesinger cycle

I obtain a political-economic (PE) cycle as a consensus of these three types of long cycles that roughly corresponds to the saeculum since 1720. Both the PE cycle and the saeculum show substantial reduction in length after the 1820's. One advantage of the PE cycle is the turning points can be objectively identified, at least for recent times. For example the start of the crisis period of the PE cycle in the economy is happened in 2008. Believing that 2001 was the 4T start, I expected this economic turning point would happen in 2001. That is a real-time event would either support or reject the 2001. It did not happen in 2001; it happened in 2008. In terms of the economy 2008 is the 4T start. As for political until the 2012 election is was still possible for 2000 to the the start of a 4T politically. When Romney lost 2000 was closed as a potential start of the political 4T. The next possible date for the political 4T start is 2008, which will be rejected in 2020 if the GOP wins both the 2016 and 2020 elections, just as the 2000 date was rejected when the Democrats won both the 2008 and 2012 elections. So you see the PE turning points can be determined objectively, no interpretation needed. Economic and stock market cycles peak when they peak and trough when they trough, the dates of these are simple facts. Also a presidential election has a winner, this too is a simple fact. And that means the start of the crisis in the PE cycle will also be a fact, not an intrepretation, as it is for the saeculum.

A second paper, The Paradigm Model, provides a model for the post-1820 PE cycle/saeculum. It requires broad political participation by all social classes and so did not start to function untill the rise of mass white suffrage in the 1820's.* It develops the theory and presents a mathematic model that can create a variety of 4T's. There is a random factor so the actual 4T that happens will be one of these, but the model puts constraints on just where a 4T can show up. All the 4T's wll not wander too far from the predicted value of 2009-33.

Past 2T and 4T equivalents in the PE cycle have all begun withing 5 years (avg. 2) of the model-predicted date. A 4T start in 2001 or before is therefore unlikley (2% probability) and so the absence of a 4T-type response to 911 is to be expected.

A third standalone paper, The Kondratiev cycle and the population stress model presents empirical support for a Kondratiev cycle that extends back to 1176. It proposes a Malthusian population-based mechanism and constructs a lagged logistics mathematical model to characterize this mechanism. This Kondratiev cycle aligns well with turnings between 1435 and 1650.

Not yet presented is a mechanism/cause for saecula/long cycles during the 1649-1822 period when neither the population nor paradigm models was operative. I'll be working on that soon.

*Acknowledgments:
In the genesis of the paradigm model key ideas were supplied by Kurt Horner and Marc Lamb. Horner suggests that the sudden shortening of cycle length in the 1820's arose from the rise of mass-suffrage. Before then he believed cycle timing was based on the age at which ruling elites came into their inheritance. Marc Lamb championed the idea that in politics and their cycles (not economics which was what I was using exclusively then) could be found the genesis of the modern saeculum. He also talked about a 40-year cycle--more on that later.