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farmer if the extra rent is less than the saving in transportation cost, move to lower rent land if the
reverse is true. Things add up: the farmers are competing for a given amount of land in each concentric
ring. The result: agriculture is arrayed in a predictable ring structure, land rents decline from the center
along a predictable bid-rent curve, and big surprise the market outcome is the efficient allocation.
A currently popular buzzword among some scientists is "emergence" a fuzzy term referring to the idea
that simple rules of individual behavior may produce quite complex aggregate outcomes that were not
obviously built into those rules, but that these complex outcomes may in turn exhibit surprising
underlying order. Well, guess what: the von Thünen model is a spectacular example of emergence.
Where was the idea of rings of activity built into the assumption of maximizing behavior by farmers?
And yet it turns out to be a hidden implication. Who would have thought that the result of a free-for-all
competition for land can be represented as the solution of an aggregate minimization problem? And yet
there it is an unexpected organizing principle. If emergence really is the kind of deep insight that some
people now claim, then von Thünen had that insight a century and a half before it became fashionable.
And indeed neoclassical economics can be regarded as one of the pioneering sciences of emergence.
Now of course the von Thünen model, like the bulk of economic models between 1820 and 1970,
focused on the case of perfect competition and constant returns. In this case the market outcome is also
the efficient plan. This will not always be true. But there is nothing about the economist's method that
necessarily restricts it to examining perfect markets and efficient outcomes. It's true that
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