Downward Causation

Discussion

Emergence and Downward Causation

Jeff Vail:

"At the cutting edge, and among the more controversial parts of Emergence theory, is the notion that "emergents bring into the world new causal powers of their own, and, in particular, theat they have the powers to influence and control the direction of the lower-level processes from which they emerge." Making Sense of Emergence, Jaegwon Kim. This notion of "downward causation" is critical. If emergents cannot exercise downward causation, then the emergent is either (1) nothing more than an as-of-yet unexplained but reducible phenomenon, or (2) useless as an ontological formulation (because what does it do or tell us?). As Jaegkown Kim asks, "For what purpose would it serve to insist on the existence of emergent properties if they were mere epiphenomena with no causal or explanatory relevance . . . [if emergence] supposes something to exist in nature which has nothing to do, no purpose to serve, a species of noblesse w hich depends on the work of its inferiors, but is kept for show and might as well, and undoubtedly would in time be abolished."

The controversy over downward causation seems to stem from the mental gymnastics demanded by a feature that emerges from itself while simultaneously influencing the sourced of its genesis--what some have suggested is an unacceptable circularity. I don't have any problem in principle with this formulation, but proponents have also developed a modification of the theory of emegence that seems to satsify even the skepitics: diachronic reflexive emergence, or emergence where the emergent at time T influences the micro-structure at T+1, which in turn results in possible modification of the emergent at T+2, etc.

Certainly, if one accepts consciousness to be an emergent, then the downward causation of consciousness (acting upon the physical body and brain structure) is clearly documented (this specific example matches the model of diachronic reflexive emergence mentioned above)." (http://www.jeffvail.net/2010/01/emergence-1-fundamentals.html)