In the present paper we illustrate an interdisciplinary didactic path of mathematics and history developed in the Mathematical High School Project (MHS). The MHS is an experimental research project developed by the research group in didactics of the Department of Mathematics of the University of Salerno (Italy). It aims to build a network of knowledge that is strictly interconnected and goes beyond the individual disciplinary themes; mathematics is « the » substratum and « the » language that creates links between the two cultures, the humanistic and the scientific ones. We analyzed the speeches of various undisputed protagonists of the last two centuries, such as Jefferson, Lincoln, Kennedy, Martin Luther King, through the lens of hypothetical-deductive logical reasoning, also making references to other areas (literary, political…) with constant links to Euclidean geometry.