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Surprisingly effective explanations for the current financial meltdown emerge from the natural sciences. A growing body of work translates insights from biology, physics and mathematics into powerful models for economic interactions.

The key element that binds these narratives together is: emergent complexity. These models skimp on explaining individual behavior. They lack a 'theory of the firm' and 'bounded rationality' concepts. Indeed, such models feature the coarsest imaginable agents, with only very rude binary (positive/negative) relationships to other agents and very rude binary (alive/dead) state.

Stringing such simplex agents together in networks that obey equally simple rules, modeling outcomes are achieved that show an uncanny resemblance to actual, historical, economic data time series. The implications are profound: individual decisions don't matter very much, the actual outcomes are determined by structural properties, i.e. by the network of interactions.

Even more mind-boggling is the cross-disciplinary reach of these effects: a stock market crash very much resembles a traffic jam very much resembles species extinction events: the mathematics is much the same in each of these very different problem domains.

This points to an underlying regularity in the laws governing complex systems, of which the economic system is but a specific manifestation. To paraphrase McLuhan: the network is the effect. It is the structure of a network, rather than the actions of network participants, that determines the eventual outcome.

The crisis on Wall Street is like a Rorschach test: it seduces people into making statements that primarily reflect their own state of mind. Everybody finds something to his liking that he latches onto.