Abstract
This paper studies the problem of the arrow of time from the scientific and philosophical perspective. The scientific section (Castagnino) poses the topic according to the instruments of measuring employed in physical theories, specially when they are applied to dynamic chaotic systems in which a temporal asymmetry is shown. From the analysis of “two schools” (epistemological and ontological), the conclusion is favorable to the reality (both ontological and epistemological) of the difference between past and future, with the recourse to Reichenbach’s notion of global system. In the philosophical section (Sanguineti) the content of the scientific part of the article is presented in a qualitative way. The role of some philosophical choices in the scientific field is stressed, taking into account the diversity of a positivistic and realistic view.