1/ "In short, the world runs on two operating systems."

A thread on @rorysutherland's thoughts in Alchemy on how the world runs on two systems: logical and psycho-logical. 2/ "The much smaller of them runs on conventional logic. If you are building a bridge or building a road, there is a definition of success that is independent of perception. Will it safely take the weight of X vehicles weighing Y kg and travelling at Z mph?

1/ On the various kinds of universality and forms of universal behaviour in #complexsystems:

'While the interactions between the components in a network have some particular nature and are governed by the corresponding laws, often we can ignore the details about them,' 2/ 'because the complex behaviour depends only on more abstract features of the interactions, such as how often they happen and between which parts.'

1/ Geoffrey West of @sfiscienceon why bigger is better in complex systems - as animals get larger, they become more efficient. Double the size of an animal, and you only have to increase it's metabolic rate by 75%. You get a 25% saving. 2/ 'despite the vagaries and accidents inherent in evolutionary dynamics, almost all of the most fundamental and complex measurable characteristics of organisms scale with size in a remarkably simple and regular fashion.

1/ The Santa Fe approach (@sfiscience) to #complexityeconomics.

'Here was this elusive "Santa Fe approach": Instead of emphasizing decreasing returns, static equilibrium, and perfect rationality, as in the neoclassical view,' 2/ 'the Santa Fe team would emphasize increasing returns, bounded rationality, and the dynamics of evolution and learning.'