yes and no

Yes and no are one of several pairs of words used to express the affirmative and the negative, respectively, in several modern languages including English.

Sic et Non, an early scholastic text whose title translates from Medieval Latin as "Yes and No", was written by Pierre Abélard. In the work, Abélard juxtaposes apparently contradictory quotations from the Church Fathers on many of the traditional topics of Christian theology. In the Prologue, Abélard outlines rules for reconciling these contradictions, the most important of which is noting the multiple significations of a single word. However, Abélard does not himself apply these rules in the body of the Sic et non, which has led scholars to conclude that the work was meant as an exercise book for students in applying dialectic (logic) to theology.

Yes and no is a system for expressing affirmative and negative in the English language.