ABSTRACT
Another aspect of complexity is revealed through cooperative behavior observed in complex dynamic networks. The flocking of birds [22], the schooling of fish [44], the swarming of insects [120], the epidemic spreading of diseases [7], the spatiotemporal activity of the brain [9, 23, 33], the flow of highway traffic [5], and the cascades of load shedding on power grids [21], these and many more complex phenomena demonstrate collective behavior. This behavior in a societal context was brilliantly articulated in the 1852 classic book Memoirs of Extraordinary Popular Delusions and the Madness of Crowds by Charles Mackay [52]:
In reading the history of nations, we find that, like individuals, they have their whims and their peculiarities, their season of excitement and recklessness, when they care not what they do. We find that whole communities suddenly fix their minds upon one object, and go mad in its pursuit: that millions of people become simultaneously impressed with one delusion, and run after it, till their attention is caught by some new folly more captivating than the first. We see one nation suddenly seized from its highest to its lowest members, with a fierce desire of military glory: another as suddenly become crazed upon a religious scruple: and neither of them recovering its senses until it has shed rivers of blood and sowed a harvest of groans and tears, to be reaped by its posterity. At an early age in the annals of Europe its population lost their wits about the sepulchre of Jesus, and crowded in frenzied multitudes to the Holy Land; another age went mad for fear of the devil......Men, it has well been said, go mad in herds, while they recover their senses slowly, and one by one...
