Social Cycles

How do social and economic cycles about?

There are quite a few cycles studied in the social sciences, e.g.

KondratievWave? (http://en.wikipedia.org/wiki/Kondratiev_wave)
BusinessCycle (http://en.wikipedia.org/wiki/Business_cycle)

An analytic models explanation this by the dynamics of supply and demand (see (German) http://de.wikipedia.org/wiki/Multiplikator-Akzelerator-Modell).

I wonder if an explanation of this based on psychology could be as follows:

Let p (n) be the number of positive (negative) ideas/memes in circulation. With positive I mean constructive, based on cooperation, synergistic. With negative I mean destructive, exploitive, parasitic. Please note, that I do not want to value these, but characterize there mode of operation.

If you assume that

The more positive memes there are, the more new positive and negative memes develop (constructive ideas give rise to further ideas, but also to ideas to exploit their effects).
The more negative memes there are, the more new negative memes develop (destructive ideas give rise to new variants of the scheme).
The more negative memes there are, the fewer new positive memes develop (because they have a less likely chance to work in a negative environment).

Mathematically:

  p' = a11*p - a12*n
  n' = a21*p + a22*n

This is a simple differential equation, that has cyclic [do you mean periodic?] solutions dependent on the aij.

Most variants on this scheme (e.g. non-linear) should be cyclic.

Does this sound plausible?

-- GunnarZarncke