Spandrels (Cocker or Springer?)
This page would appear to be as good a place as any to explain the concept of a spandrel. Anyone want to give it a shot? I'm not sure I can explain it coherently. I can, however, set up a redirect... EVDebs (talk) 04:23, 31 August 2010 (UTC)
The defining point about emergent behaviours is that there is no possible description or predictive construction 'from the bottom up', using the known properties of the components and the defined rules of their interactions, that proceeds in fewer steps than the occurrence of the emergent phenomenon.
That is to say: the existence of a strongly emergent phenomenon contradicts reductionism. Many behaviours in rules-based systems have complex results that yield to a reductionist approach, and can fully-described in one or or two lines of mathematical argument that fully predict the final state - a state which might, like a Fractal 'art' piece, require vast amounts of information to describe.
This complex final state is therefore not 'emergent' - it is intrinsic to and wholly described within a description of the components, their rules of interaction, and a short algorithm.
But the 'puffing train' (and the 'flock of geese' in Langton's Ant) are irreducible: all attempts at predicting the final state from first principles fail to arrive at the final state in fewer steps than simply running the simulation. That is to say: the complex information content of the final state has 'emerged' - it has, in violation of all precepts of reductionist logic, 'appeared from nowhere' . Or at least, appeared from somewhere that did not contain sufficient information to describe it.
Could one of the resident experts return to this section and expand on this point with a few references from Langton's original papers? The point is worth labouring - I would say it is worth belabouring the reader - because the current wording is a little too bland and a nonspecialist reader would fail to recognise its significance.
Apologies for the anonymous posting. The academic community that I belong to is somewhat intolerant of modern media and has only recently - and reluctantly! - approved the use of goose-feather quills for writing. — Unsigned, by: 188.8.131.52 / talk / contribs 13:56, 28 December 2010 (UTC)