"A still more extreme thesis is proposed by rational expectations theoreticians, among whom is the American Robert Lucas (b. 1937, Nobel prize in 1995). In a 1972 article, Lucas joined the assumption of markets in continuous equilibrium with that of rational expectations, originally formulated by Muth (1961), according to which ‘expectations [...] are essentially the same as the predictions of the relevant economic theory’. As a consequence, economic agents learn to take account of public intervention in the economy, discounting its effects beforehand. Thus, for instance, deficit public expenditure, that is not financed by a contemporary increase in taxation, adopted by the government to stimulate aggregate demand, is counterbalanced by a reduction in private consumption, decided by private economic agents to put aside the savings with which to pay for the taxes which sooner or later will have to be introduced to pay for the public debt with which public expenditure is financed. In this context, the Phillips curve turns out to be vertical also in the short run: expansionary monetary and fiscal policy interventions may only produce an increase in the rate of inflation, not in the level of employment. … The rational expectations assumption, in the usual context of a one commodity model, also underlies a new theory of the trade cycle, the ‘real cycle theory’. After dominating the scene in the 1980s, in the following decade rational expectations theory gradually lost ground, even if in the theoretical confrontation with representatives of the neoclassical synthesis the shaky nature of its theoretical foundations – the one-commodity model, common to their rivals too – has not been stressed."