Emergent complexity: what uphill analysis or downhill invention can not   do
  In these notes we review emergent phenomena in complex systems, emphasizing ways to identify potential underlying universal mechanisms that generates complexity. The discussion is centered around the emergence of collective behavior in dynamical systems when they are poised near a critical point of a phase transition, either by tuning or by self-organization. We then argue the rationale for our proposal that the brain is naturally poised near criticality reviewing recent results as well as the implications of this view of the functioning brain. 
Dante R. Chialvo