International Encyclopedia of Systems and Cybernetics

1. "The spontaneous transformation of a set of components from a less coherent state, where the space-time correlation between them is confined to mean free path and mean relaxation collision times, to a more coherent state exhibiting novel, global, dynamical space-time behavior" (R. SWENSON, 1989, p.188).

2. "Any process whereby the variety and/or constraint of a system changes" (F. HEYLIGHEN, pers. comm.).

Emergence implies discontinuity and innovation in the construction of complexity (W. KARGL, 1991, p.579).

G. PASK, for instance described functional emergence as the recognition "by an external observer" that "a device or agent has acquired a new distinction, concept, structure" (P. CARIANI, 1993, p.28).

SWENSON comments that this new coherent state is: "many order of magnitude greater than mean free path and relaxation times; inaccessible to, not locatable in, and not reducible to the individual or summative behavior of the separated atomisms" (i.e. elements or components); "the spontaneous creation of a new set of macroscopic constraints that reduce accessible microstates from some initial set Mn to some much smaller subset Ms, to yield a new irreducible level of dynamical space-time behavior. By the transformation Mn to Ms, emergence is always a progressive, asymmetrical time-dependent transformation of matter away from equilibrium" (p.189).

Emergent systems are thus always more complex and less stable than their components. They derive from the appearance of an emergent attractor. Ch. LAVILLE's concepts about vortexes (1950), and recently D. McNEIL toroidal model of the system (1993a and b), suggest that such attractors are produced by opposing energetic fields.

HEYLIGHEN states: "The emergence of systems of (partially) conserved distinctions cannot be deduced from the properties of lower-level "microscopic" distinctions, but may be understood as a process of self-organization, governed by variation and selective retention" (1989, p.382).

J.P. CHANGEUX in turn states: "The highest levels (of organization) emerge progressively throughout biological evolution. They superpose and embed the inferior levels, themselves selected during former evolutive steps (1992, p.707).

HEYLIGHEN also writes: "… such a process will necessarily change the identity of the system itself. It might therefore also be called a system transition. This is a qualitative change, where a new organization or system appears, with properties (potential appearances) that did not exist in the old system. The more usual ("quantitative") dynamical evolution of a system, on the other hand, is merely a transition within the constrained variety of possible appearances, where neither constraint nor variety undergo any change" (Ibid).

This concept is quite different from SWENSON's, but closer to PRIGOGINE's. Here dynamical evolution (or better, adaptation or accomodation) remains in accordance with the organizational closure of the system, which is replaced, or at least transformed, in case of emergence.

Examples may better emphasize differences.

A running athlete accomodates him/herself to the effort by breathing rapidly and strongly, but only for a short time.

One who must go to live for years in some high altitude place, adapts permanently his/her respiratory capacity to this change.

The first animals who left the oceans underwent a radiative evolution of emergent types, changing branchial for aerial pulmonar breathing.