Agnosticism and atheism are two positions in regard to the world that distance themselves from a theistic or religious posture; although their definition is not based exclusively on the negation of a God or on the lack of religious beliefs, rather, they imply a set of values and representations of a different kind, as well as practical consequences in the actions of agnostic or atheistic people. Although these positions are usually considered homogeneously, there are important differences among them. This article talks about those positions in the case of Mexico.