Abstract

Since the origins of the notion of emergence in attempts to recover the content of vitalistic anti-reductionism without its questionable metaphysics, emergence has been treated in terms of logical properties. This approach was doomed to failure, because logical properties are either sui generis or they are constructions from other logical properties. If the former, they do not explain on their own and are inevitably somewhat arbitrary (the problem with the related concept of supervenience, Collier, 1988a), but if the latter, reducibility is assured because logical constructs are reducible, by definition, to their logical components. A satisfactory account of emergence must recognise that it is a dynamical, not a logical property of property of natural systems, and that its basis is dynamical rather than logical composition. Collier (1988a) introduced the concept of cohesion as the closure of the causal relations among the dynamical parts of a dynamical particular that determine its resistance to external and internal fluctuations that might disrupt its integrity. Cohesion is an equivalence relation that partitions a set of dynamical particulars into unified and distinct entities, providing the identity conditions for such particulars. Cohesion blocks reduction of dynamical particulars, and is necessary for dynamical emergence. We will give reasons for thinking that cohesion might be sufficient for emergence as well.