In this assay I show as the thought occidental person entered in crisis with the advent of the after-modern philosophy, that questions all our capacity to know. Such line of thought, argument, has its origin in a rejection to the iluminista thought of century 18. Its posterior development if gave through the romantismo culminating with Nietzsche, in the end of century 19. This thinker is in the bases of all the relativista thought/after-modernista of century 20. A new line of thought of the human being, however, is if consolidating through natural sciences, bringing a gust of renewal in this area. Until few decades, science was intent in objects of study as physical, chemical, biology, astronomy, among others things that are external to ‘ ‘ esprito’ ‘ human being.
Science human being who it recognized and accepted was the behaviorista psychology, that, we know today, it very presented a precarious model of theory of the mind, and many scientists believed that mental phenomena were subjects that had to be left to the incubency of the philosophy and religion. But finally, especially from the decade of 1980, science started if to come back toward a rigorous study of the human being, discovering doors that had been never before opened, allowing a bigger understanding of this creature. The consequences of such enterprise are producing a radical reformularization in our vision of the human being, opening way for a new school of social thought..