<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-06-28T20:10:00Z</responseDate><request verb="GetRecord" identifier="oai:docta.ucm.es:20.500.14352/98454" metadataPrefix="qdc">https://docta.ucm.es/rest/oai/request</request><GetRecord><record><header><identifier>oai:docta.ucm.es:20.500.14352/98454</identifier><datestamp>2025-02-03T16:25:40Z</datestamp><setSpec>com_20.500.14352_14</setSpec><setSpec>col_20.500.14352_15</setSpec></header><metadata><qdc:qualifieddc xmlns:qdc="http://dspace.org/qualifieddc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://purl.org/dc/elements/1.1/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dc.xsd http://purl.org/dc/terms/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dcterms.xsd http://dspace.org/qualifieddc/ http://www.ukoln.ac.uk/metadata/dcmi/xmlschema/qualifieddc.xsd">
   <dc:title>Many-Sorted Logic</dc:title>
   <dc:creator>Manzano Arjona, María Gracia</dc:creator>
   <dc:creator>Aranda Utrero, Víctor</dc:creator>
   <dc:contributor>Zalta, Edward </dc:contributor>
   <dc:contributor>Nodelman, Uri</dc:contributor>
   <dcterms:abstract>Classical logic is the appropriate formal language for describing mathematical structures containing a single universe or domain of discourse. By contrast, many-sorted logic (MSL) allows quantification over a variety of domains (called sorts). For this reason, it is a suitable vehicle for dealing with statements concerning different types of objects, which are ubiquitous in mathematics, philosophy, computer science, and formal semantics. Each sort groups a unique category of objects (for example, points and straight lines are different types of objects in a 2-sorted structure).

Despite the addition of this expressive resource, many-sorted logic “stays inside” first-order logic, so the main metatheorems (completeness, interpolation, and so on) can be proved. Many-sorted logic also serves as a unifying framework for translating various logical systems; for instance, some intensional and higher-order logics have natural translations into many-sorted logic. Many-sorted first-order logic can be reduced to one-sorted first-order logic, both syntactically and semantically. Many-sorted first-order logic can also be extended to a many-sorted second-order logic called “sort logic”.

An axiomatic calculus for many-sorted logic was introduced by Hao Wang in Wang (1952), where he made a comparison between one-sorted and many-sorted theories. In 1967, Solomon Feferman gave a sequent calculus for many-sorted logic, proving not only its completeness but also the cut elimination and interpolation theorems (Feferman 1968). Feferman (2008) summarizes some applications of the many-sorted interpolation theorems to model theory. (See the supplement on early history for more information.)

Section 1 lays out the basics of many-sorted logic, presenting some examples and explaining how the formal language, structures, and semantics differ or not from classical logic. Section 2 explains how to modify a one-sorted first-order calculus to obtain a many-sorted version; also, completeness is treated and some automated theorem provers are mentioned. Section 3 describes a plan on which many-sorted logic serves as a common framework for translating a variety of logical systems. Sections 4 and 5 apply this plan to second-order logic and non-classical logics (modal and dynamic logic), respectively. Finally, section 6 comments on further results in many-sorted logic.</dcterms:abstract>
   <dcterms:dateAccepted>2024-02-02T17:10:32Z</dcterms:dateAccepted>
   <dcterms:available>2024-02-02T17:10:32Z</dcterms:available>
   <dcterms:created>2024-02-02T17:10:32Z</dcterms:created>
   <dcterms:issued>2022</dcterms:issued>
   <dc:type>book part</dc:type>
   <dc:identifier>https://hdl.handle.net/20.500.14352/98454</dc:identifier>
   <dc:identifier>1095-5054</dc:identifier>
   <dc:language>eng</dc:language>
   <dc:relation>Manzano, María and Víctor Aranda, "Many-Sorted Logic", The Stanford Encyclopedia of Philosophy (Winter 2022 Edition), Edward N. Zalta &amp; Uri Nodelman (eds.), URL = &lt;https://plato.stanford.edu/archives/win2022/entries/logic-many-sorted/>.</dc:relation>
   <dc:rights>http://creativecommons.org/licenses/by-nc-nd/4.0/</dc:rights>
   <dc:rights>metadata only access</dc:rights>
   <dc:rights>Attribution-NonCommercial-NoDerivatives 4.0 International</dc:rights>
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