Comment: This article introduces all the necessary tools in order to understand both the proof-theoretic and the model-theoretic aspects of first-order classical logical consequence. As such it can be used as a main reading in an introductory logic course covering classical first-order logic (assuming the students will have already looked at classical propositional logic). Moreover, the article covers some metatheoretic results (soundness, completeness, compactness, upward and downward Löwenheim-Skolem), which makes it suitable as a reading for a slightly more advanced course in logic. Finally, the article includes a brief incursion into the topic of logical pluralism. This makes it suitable to be used in a course on non-classical logics with an introduction module on classical logic.
2018, The Stanford Encyclopedia of Philosophy, Edward N. Zalta (ed.)
Added by: Berta Grimau
Summary: This article provides the basics of a typical logic, sometimes called 'classical elementary logic' or 'classical first-order logic', in a rigorous yet accessible manner. Section 2 develops a formal language, with a syntax and grammar. Section 3 sets up a deductive system for the language, in the spirit of natural deduction. Section 4 provides a model-theoretic semantics. Section 5 turns to the relationships between the deductive system and the semantics, and in particular, the relationship between derivability and validity. The authors show that an argument is derivable only if it is valid (soundness). Then they establish a converse: that an argument is valid only if it is derivable (completeness). They also briefly indicate other features of the logic, some of which are corollaries to soundness and completeness. The final section, Section 6, is devoted to a brief examination of the philosophical position that classical logic is 'the one right logic'.
Export citation in BibTeX format
Export text citation
View this text on PhilPapers
Export citation in Reference Manager format
Export citation in EndNote format
Export citation in Zotero format