"The book is well written and accessible; it introduces, and offers a philosophical commentary on, the main formal tools developed by logicians over the past 140 years or so. In doing so, it covers philosophically important topics such as the interpretation of variables, higher-order logics, universal algebra, and the correspondence between valuations and deductive calculi in propositional logic." – Notre Dame Philosophical Reviews"In a tour-de-force survey of logical systems, Peregrin addresses the fundamental question of how logical systems relate to natural langue argumentation. The book develops the view that logical systems are models and challenges widespread assumptions about the nature of logical semantics." – Georg Brun, University of Bern"For the general student of philosophy or linguistics it is hard to understand why to do formal logics at all. By using a rule-theoretical access, Peregrin’s book shows step by step how ideal models are necessary tools for understanding the form of valid reasoning, but no first results in a meliorating project of replacing natural by formal languages." – Pirmin Stekeler-Weithofer, University of Leipzig