Dados, vol.54, n.2, 2011: pp. 223-258.
Democracy became the preferred and form of government only in the twentieth century. The new historical fact that led to the change of preference was the capitalist revolution, which changed the manner of appropriating economic surplus from violence to the market. The disappearance of the fear of expropriation, the rise of middle classes and the pressures of the poor are the second, third and fourth new historical facts that opened the way for the transition democracy. After these four conditions were fulfilled, universal suffrage was granted. The theory presented here does not predict transitions, since countries often turn democratic without fully realized historical conditions, but it predicts democratic consolidation, since no country that has completed its capitalist revolution falls back into authoritarianism.