Perhaps the most elaborate recent definition of emergence was provided by Jeffrey Goldstein in the inaugural issue of Emergence.(Goldstein 1999) To Goldstein, emergence refers to "the arising of novel and coherent structures, patterns and properties during the process of self-organization in complex systems." The common characteristics are:

(1) radical novelty (features not previously observed in systems);
(2) coherence or correlation (meaning integrated wholes that maintain themselves over some period of time);
(3) A global or macro "level" (i.e. there is some property of "wholeness");
(4) it is the product of a dynamical process (it evolves); and
(5) it is "ostensive" - it can be perceived.

For good measure, Goldstein throws in [supervenience] -- downward causation.

Tomado de la wikipedia