So what is populism? Is it an ideology, a social movement, a form of leadership, or a political regime? Resuming the intuition and the title of Laclau’s work, The populist reason, which collects thirty years of study about Latin American experience, we tried to answer to this question by re-examining all the stages of philosophical and sociological speculation, highlighting the polysemic aspects that make it hardly ascribable to a unit, even rhetorical-exhibit. From the backdrop of the processes of modernization to the logic of political action, populism needs to be read as a true political theory without that denigrating attitude that relegated it into a subordinate and pathological status. Populism is therefore a political experiment, the result of the eloquence of the elites and of a personalistic politics, which today finds its roots in contemporary democracies. Instead of a rational model that has long read populism in terms of lack of illness, incurable incurability, today we pro-pose to broaden our vision and consider populism as a possible structuring of political life.