Fixing the point: the contribution of early game theory to the tool-box of modern economics

The paper aims at reconstructing the sequence of works through which the fixed-point technique entered the tool-box of modern economics and at establishing a link between this sequence and the neoclassical approach to economic modeling. The focus is on the change in the demonstration techniques caused by the spread of the so-called formalist approach to mathematical economics; this change was embodied by the fixed-point technique. The main conclusions of the paper are that the formalist revolution marked a dramatic discontinuity in the history of economic theory and that early game theory - despite having been the gateway through which the fixed-point entered economics - was only partly responsible for such a discontinuity.