International Encyclopedia of Systems and Cybernetics

"The belief that the future state of a system is completely determined by its present state, the same causes producing the same effects" (E. SCHWARZ, 1993, p.4).

This at least, is a definition specifically formulated in relation to systems.

SCHWARZ states, rightly it seems, that determinism is a belief, resulting of an epistemological attitude.

Determinism is one of the most abstract and ill-interpreted concepts in the history of science and philosophy. As noted by G. ISRAEL, numerous definitions have been given and the concept appears on different conceptual levels (1992, p.252).

Misunderstandings about determinism lead easily to misinterpretations about complex systems behavior. While necessarily very sketchy and inconclusive, a discussion of the subject is unavoidable.

To begin with, determinism cannot be reduced to a principle of absolute causality, that has been"… the dominant metaphysics of modern science" (p.253).

The word appears in Germany during the 18th Century (LEIBNIZ), but is imposed by Cl. BERNARD in France, around 1860: "There is an absolute determinism in all sciences ", or "It should be admitted as an experimental axiom that in living beings as well as in raw substances, the conditions for the existence of any phenomenon are determined in an absolute manner" (1952, p.111). He however repented somewhat later on: "When I introduced for the first time the word determinism… I was not thinking that it could be confused with LEIBNIZ philosophical determinism" (1878, p.55)… However, it was!

G. ISRAEL concludes: "Last century's scientific determinism is an epistemologic doctrine deriving from CI. BERNARD's thesis" (p.257). As a result, determinism seemed to have an absolute ontologie value.

No significant problem emerged from this viewpoint as long as science was directed to the study of linear or reducible to linear processes. The difficulties started on one hand with BOLTZMANN's statistical thermodynamics, and on the other with POINCARÉ's 3 bodies problem, which was a harbinger of chaotic behavior of systems with sensibility to initial conditions.

Thus seemingly random transformations in the systems behavior started to mix a statistical aspect with a kind of diffuse surviving determinism. As with quanta, relativity and Prigoginian thermodynamics, clearcut, absolutist concepts of the past have to give way to more intricated and subtle models. "Cause" becomes now a complex web of causes and determinism becomes at the same time diffuse and generalized in space and time. It must finally be admitted that science only constructs general models, while any concrete phenomenon is a particular case, because it is a specific result of a unique, but complex history.