ABSTRACT
In the 1950s, as the early versions of the Arrow Debreu (A-D) model were being published, a number of high-profile proponents of the Chicago School, well known for their pro-market affinities, developed Marshallian models of market adjustment. The full development of axiomatic general equilibrium theory and the selectionist arguments of the Chicago approach read against the background of a widespread tendency within the neoclassical tradition to assume as little as possible about the human subject. Accordingly, the proponent's of late neoclassical economics, to the extent that they define themselves in opposition to the A-D model, tend to affirm selections arguments and renounce general equilibrium modeling. Not unlike the way early neoclassical economics gained something extra e.g., scientific credibility by borrowing concepts from physics, the post-war and late neoclassical tradition has gained something extra from toying with biological analogies: the elevation of competition to an ontological status.
