The Kondratieff wave cycle goes through four distinct phases of beneficial inflation (spring), stagflation (summer), beneficial deflation (autumn), and deflation (winter). Since, the last Kontratyev cycle ended around 1949, we have seen beneficial inflation 1949-1966, stagflation 1966-1982, beneficial deflation 1982-2000 and according to Kondratieff, we are now in the (winter) deflation cycle which should lead to depression.By this, the depression cycle should last from 2001-2020, more or less, since all the other "winter" periods lasted about 20 years. Is it any coincidence that 2008 is close to the dead center of that range? I think not. This also implies that there will be a beneficial inflation 2020-2035/40. Given the degree of quantitive easing in which the Fed engaged, I think there is little doubt that inflation will be on the horizon. One hopes it will in fact be beneficial.
Coincidentally, Turchin's secular cycles, when mapped onto the K-waves, give interesting patterns.
1970 was in the middle of a stagflation period.
1920 was at the end of a stagflation period.
1870 was during Reconstruction, near the end of a plateau leading to depression.
1820 was at the beginning of a plateau, during the "Era of Good Feelings" -- a time, coincidentally, when there was not a peak of violence.
1770 was in a depression cycle, and of course was the lead-in to the Revolutionary War.
2020 will come at the end of our depression cycle, at the opening of an expansionary period.
It is my suspicion that 2020 will also do a number of other things. It will be the swan song of the social conservatives and of the kinds of nationalist sentiments being fostered by Trump and Sanders. It will also spell the end of our Egalitarianist society (in Gravesean terms), and the emergence of an Integrationist society. Given that this means a tier-leap, meaning an exponential leap, it would not be surprising to me if we will be facing the kind of revolutionary violence as we saw in the American and French Revolutions. The former moved the U.S. into a more liberal society (entrepreneurial level), while the latter attempted to move French society into an Egalitarian society (failing, because it attempted to skip a level).
We saw in 1920 and 1970 egalitarian upheavals, with the first one applying pretty much only to white males, with the latter expanding the franchise to minorities of all kinds.
2020, I suspect, will be an Integrationist upheaval, perhaps first only affecting the West, perhaps also including economies like China and India, with the rest of the world being included in 2070. Perhaps, though, 2070 will be a Holistic upheaval, since there is good evidence that increasing complexity evolves ever-more quickly over time.
But if 2020 is in fact an Integrationist upheaval, creating an Integrationist society to replace the Egalitarian society in which we currently reside, I suspect that 2020 will make the violence of 1970 and 1920 look like cake walks. The aftermath, however, will give us a radically different society than the one we have. We will see the final breakdown of hierarchical organization and the more widespread embrace of scale free network processes. We aren't talking about the false kinds embraced by the egalitarians, whose flattened hierarchies are still hierarchies, but real scale free networks with nobody really in charge, just algorithms aiding smooth coordination. Think Uber applied to the entire economy, to the degree that it is possible to do so.
Such a society is more accepting of differences, heterogeneity, complexity, uncertainty, ambiguity, and change. It is more cosmopolitan, favoring diversity and movement over artificially created political boundaries. Such a society will be more interested in information and the accumulation and use of information. It will be interested in both micro and macro views of life, mind, and society, recognizing the necessary interactions between those views and among those aspects. Such a society will recognize the negative feedback dominating at the micro social level and the positive feedback dominating at the macro social level, and the bipolar feedback driving complexity of society in their necessary interactions. In other words, such a society will finally come to terms with the fact that all elements of human society are spontaneous orders.
In fact, we have to understand these interacting elements if we are going to understand the interactions of these macro-level social patterns. With a macro-only view, we would expect to just see cycle-after-cycle going on into infinity without change. But I suspect that we have seen these saves -- K-waves and secular cycles -- shortening over time. Why? Because these waves are taking place in societies which have different features due to emergent complexity. Greater complexity shortens the temporal experience of that process. Interacting negative and positive feedback give rise to biotic processes with the property of being able to leap into a new level of complexity. Combine the micro patterns of human interactions giving rise to negative feedback with the macro patterns giving rise to positive feedback, and you get the bipolar feedback described by Hector Sabelli.
If you want a more accurate understanding of the evolution of our social world, I think we have to combine the work of J.T. Fraser, Kondratieff, Hector Sabelli, F.A. Hayek, Clare Graves, and Peter Turchin. If this gives rise to a model of society that is insanely complex, well, that just means we're finally on the right track.