A structure of pre-predicative ideation upon which other apparently “rational” structures are erected. B. determines the field or perspective chosen, from which an idea or a system of ideas is developed. In the case of dialogue, even the most rational, the parties take for granted certain undemonstrated propositions, and make use of them without examination. We call such assumptions “pre-dialogal.” Beliefs determine practices and customs as well as the organization of language, or the illusion of a world that is accepted as “real” but is observed from the limited parameters determined by a particular historical perspective. Any such perspective typically tends to exclude others. As the historical “level” of the generations changes, so does the system of beliefs, which also involves a change in the perspective, the “point from which” one is able or willing to observe the world (personal, social, scientific, historical, etc.). This change of perspective is what allows the emergence of new ideas. These new ideas take root in the new historical level, and copresently establish new pre-predicates, new propositions that then become incontestable and in turn give rise to new beliefs. As an example we can consider a behavior common in the West until only recently: the affirmation that certain knowledge or information was “scientific” was all that was required to defend a given position and to discredit an opposing one as “unscientific” (science). Several generations remained mired in this dispute, until the b. on which their scientistic artifices were based itself became subject to debate. When it came to be understood that every scientific theory was, at bottom, a construction of approximation to reality and not reality itself, this rigidly scientistic perspective began to change. However, this change in turn opened the way for the emergence of neo-irrationalist currents of thought.