Introduction to binary relations: definitions, examples, and properties of relations. We'll build on these ideas in subsequent videos about preferences, utility-function representations of preferences, equivalence relations and partitions, and information structures in economics and game theory. This video is a continuation of the video Binary Relations (A). When talking about the asymmetric and antisymmetric properties in this video, I refer to the concepts of antecedent and consequent in an implication, and to statements that are vacuously true, and to the contrapositive of an implication. If these terms and concepts are unfamiliar to you, take a look at Lectures 6(B) and 6(C) on logic and implication.