How do we approach the question of an alternative develop ment (for the Third World no less than for the First) in ways that go beyond mere literary utopias? This essay seeks to ex plore this question by examining the kinds of behavior that are revealed as the so-called popular classes of Latin Ameri can cities confront their daily struggles of survival and liveli hood. It is agued that their behavior reflects an existential Reason that must be balanced off against the cognitive Rea son which underlies the Enlightenment model ofmoderniza tion. Four aspects of this model are examined: in metaphys ics, epistemology, philosophical anthropology, and the legal political order. The essay concludes by aguing that existen tial and cognitive Reason stand in a dialectical relationship where each defines and sets limits to the other, thus preven ting the totalization of any model, including the hegemonic model of capitalist modernization.