Semantic games are an important evaluation method for a wide range of logical languages, and are frequently resorted to when traditional methods do not easily apply. A case in point is a family of independence-friendly (IF) logics which allow regulation over information flow in formulas, and thus perfect information fails in the games associated with such formulas. This mechanism of imperfect information is studied in this paper. It is noted that imperfect information of players often gives rise to the game-theoretic phenomenon of imperfect recall. Furthermore, independence-friendliness in epistemic logic is investigated. We also discuss a couple of misunderstandings that have occurred in the literature concerning IF first-order logics and gametheoretical semantics, related to such issues as intuitionism, constructivism, truth-definitions, mathematical prose, and the status of set theory. By straighten out these misunderstandings, we hope to show the importance of the role semantics ga...

Scientific discourse leaves implicit a vast amount of knowledge, assumes that this background knowledge is taken into account—even taken for granted—and treated as undisputed. In particular, the terminology in the empirical sciences is treated as antecedently understood. The background knowledge surrounding a theory is usually assumed to be true or approximately true. This is in sharp contrast with logic, which explicitly ignores underlying presuppositions and assumes uninterpreted languages. We discuss the problems that background knowledge may cause for the formalization of scientific theories. In particular, we will show how some of these problems can be addressed in the context of the computational representation of scientific theories.