How We Believe_ Science and the Search for God - Michael Shermer [139]
Corollary 6: Between origin and bifurcation, sequences self-organize through the interaction of contingencies and necessities in a feedback loop driven by the rate of information exchange. In other words, the hewing of a historical channel is driven by a feedback mechanism between the forces within the system and the forces without—think of mass hysterias and witch hunts that feed on themselves, with the exchange of information among accusers, informants, victims, and bystanders driving the system faster and deeper until it collapses.
At the beginning of a historical sequence, actions of the individual elements (atoms, molecules, organisms, people) are chaotic, unpredictable, and have a powerful influence on the future development of that sequence. But as the sequence slowly but ineluctably evolves, and the pathways become more worn, the chaotic system self-organizes into an orderly one. The individual elements sort themselves, and are sorted into their allotted positions, as dictated by what came before, with the conjuncture of events compelling a certain course of action by constraining prior conditions—contingent-necessity.
In the language of contingent-necessity, a bifurcation, or “trigger of change,” is any stimulus that causes a shift from the dominance of necessity and order to the dominance of contingency and chaos in a historical sequence, such as inventions, discoveries, economic and political revolutions, war, famine and disease, immigrations and emigrations, and so on. A trigger of change, however, will not cause a shift at just any point in the sequence. Corollary 5 states that it will be most effective when well-established necessities have been challenged by others so that a contingency may push the sequence in one direction or the other. This trigger point is any point in a historical sequence where previously well-established necessities have been challenged by others so that a trigger of change (contingency] may push the sequence in one direction or the other. Similarly, the butterfly effect, or the trigger effect—described in Corollaries 1 and 2—is the cascading consequences of a contingent trigger of change in a historical sequence. The power of the trigger depends on when in the chronological sequence it enters. The flap of the butterfly’s wings in Brazil may indeed set off a tornado in Texas, but only when the system has started anew or is precariously hanging in the balance. Once the storm is well under way, the flap of a million butterfly wings would not alter the outcome for the tornado-leery Texans. The potency of the sequence grows over time.
Corollary 6 describes feedback systems whose outputs are connected to their inputs in such a manner that there is constant change in response to both, like microphone feedback in a P.A. system. The mechanism that drives the feedback loop is the rate of information exchange, as in the stock market that booms and busts in response to a flurry of buying or selling, or social movements such as witch crazes that self-organize, grow, reach a peak, and then collapse, all described by Corollaries 1 to 6.
Chaos theory and the model of contingent-necessity describe change in the same manner, as the Nobel laureate Ilya Prigogine notes when observing that in chaos the “mixture of necessity and chance constitutes the history of the system.” Similarly, necessity and contingency are the shaping forces for historical sequences—humans making their own history but not just as they please. According to Prigogine, all systems, including historical ones, contain subsystems that are “fluctuating.” As long as the fluctuations