CS 6110 S17 Lecture 29 Propositions As Types, Continued 1 a Digression
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Chapter 18 Negation
Chapter 18 Negation Jong-Bok Kim Kyung Hee University, Seoul Each language has a way to express (sentential) negation that reverses the truth value of a certain sentence, but employs language-particular expressions and gram- matical strategies. There are four main types of negatives in expressing sentential negation: the adverbial negative, the morphological negative, the negative auxil- iary verb, and the preverbal negative. This chapter discusses HPSG analyses for these four strategies in marking sentential negation. 1 Modes of expressing negation There are four main types of negative markers in expressing negation in lan- guages: the morphological negative, the negative auxiliary verb, the adverbial negative, and the clitic-like preverbal negative (see Dahl 1979; Payne 1985; Zanut- tini 2001; Dryer 2005).1 Each of these types is illustrated in the following: (1) a. Ali elmalar-i ser-me-di-;. (Turkish) Ali apples-ACC like-NEG-PST-3SG ‘Ali didn’t like apples.’ b. sensayng-nim-i o-ci anh-usi-ess-ta. (Korean) teacher-HON-NOM come-CONN NEG-HON-PST-DECL ‘The teacher didn’t come.’ c. Dominique (n’) écrivait pas de lettre. (French) Dominique NEG wrote NEG of letter ‘Dominique did not write a letter.’ 1The term negator or negative marker is a cover term for any linguistic expression functioning as sentential negation. Jong-Bok Kim. 2021. Negation. In Stefan Müller, Anne Abeillé, Robert D. Borsley & Jean- Pierre Koenig (eds.), Head-Driven Phrase Structure Grammar: The handbook. Prepublished version. Berlin: Language Science Press. [Pre- liminary page numbering] Jong-Bok Kim d. Gianni non legge articoli di sintassi. (Italian) Gianni NEG reads articles of syntax ‘Gianni doesn’t read syntax articles.’ As shown in (1a), languages like Turkish have typical examples of morphological negatives where negation is expressed by an inflectional category realized on the verb by affixation. -
Continuation-Passing Style
Continuation-Passing Style CS 6520, Spring 2002 1 Continuations and Accumulators In our exploration of machines for ISWIM, we saw how to explicitly track the current continuation for a computation (Chapter 8 of the notes). Roughly, the continuation reflects the control stack in a real machine, including virtual machines such as the JVM. However, accurately reflecting the \memory" use of textual ISWIM requires an implementation different that from that of languages like Java. The ISWIM machine must extend the continuation when evaluating an argument sub-expression, instead of when calling a function. In particular, function calls in tail position require no extension of the continuation. One result is that we can write \loops" using λ and application, instead of a special for form. In considering the implications of tail calls, we saw that some non-loop expressions can be converted to loops. For example, the Scheme program (define (sum n) (if (zero? n) 0 (+ n (sum (sub1 n))))) (sum 1000) requires a control stack of depth 1000 to handle the build-up of additions surrounding the recursive call to sum, but (define (sum2 n r) (if (zero? n) r (sum2 (sub1 n) (+ r n)))) (sum2 1000 0) computes the same result with a control stack of depth 1, because the result of a recursive call to sum2 produces the final result for the enclosing call to sum2 . Is this magic, or is sum somehow special? The sum function is slightly special: sum2 can keep an accumulated total, instead of waiting for all numbers before starting to add them, because addition is commutative. -
Denotational Semantics
Denotational Semantics CS 6520, Spring 2006 1 Denotations So far in class, we have studied operational semantics in depth. In operational semantics, we define a language by describing the way that it behaves. In a sense, no attempt is made to attach a “meaning” to terms, outside the way that they are evaluated. For example, the symbol ’elephant doesn’t mean anything in particular within the language; it’s up to a programmer to mentally associate meaning to the symbol while defining a program useful for zookeeppers. Similarly, the definition of a sort function has no inherent meaning in the operational view outside of a particular program. Nevertheless, the programmer knows that sort manipulates lists in a useful way: it makes animals in a list easier for a zookeeper to find. In denotational semantics, we define a language by assigning a mathematical meaning to functions; i.e., we say that each expression denotes a particular mathematical object. We might say, for example, that a sort implementation denotes the mathematical sort function, which has certain properties independent of the programming language used to implement it. In other words, operational semantics defines evaluation by sourceExpression1 −→ sourceExpression2 whereas denotational semantics defines evaluation by means means sourceExpression1 → mathematicalEntity1 = mathematicalEntity2 ← sourceExpression2 One advantage of the denotational approach is that we can exploit existing theories by mapping source expressions to mathematical objects in the theory. The denotation of expressions in a language is typically defined using a structurally-recursive definition over expressions. By convention, if e is a source expression, then [[e]] means “the denotation of e”, or “the mathematical object represented by e”. -
A First Introduction to the Algebra of Sentences
A First Introduction to the Algebra of Sentences Silvio Ghilardi Dipartimento di Scienze dell'Informazione, Universit`adegli Studi di Milano September 2000 These notes cover the content of a basic course in propositional alge- braic logic given by the author at the italian School of Logic held in Cesena, September 18-23, 2000. They are addressed to people having few background in Symbolic Logic and they are mostly intended to develop algebraic methods for establishing basic metamathematical results (like representation theory and completeness, ¯nite model property, disjunction property, Beth de¯n- ability and Craig interpolation). For the sake of simplicity, only the case of propositional intuitionistic logic is covered, although the methods we are explaining apply to other logics (e.g. modal) with minor modi¯cations. The purity and the conceptual clarity of such methods is our main concern; for these reasons we shall feel free to apply basic mathematical tools from cate- gory theory. The choice of the material and the presentation style for a basic course are always motivated by the occasion and by the lecturer's taste (that's the only reason why they might be stimulating) and these notes follow such a rule. They are expecially intended to provide an introduction to category theoretic methods, by applying them to topics suggested by propositional logic. Unfortunately, time was not su±cient to the author to include all material he planned to include; for this reason, important and interesting develope- ments are mentioned in the ¯nal Section of these notes, where the reader can however only ¯nd suggestions for further readings. -
A Symmetric Lambda-Calculus Corresponding to the Negation
A Symmetric Lambda-Calculus Corresponding to the Negation-Free Bilateral Natural Deduction Tatsuya Abe Software Technology and Artificial Intelligence Research Laboratory, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba, 275-0016, Japan [email protected] Daisuke Kimura Department of Information Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba, 274-8510, Japan [email protected] Abstract Filinski constructed a symmetric lambda-calculus consisting of expressions and continuations which are symmetric, and functions which have duality. In his calculus, functions can be encoded to expressions and continuations using primitive operators. That is, the duality of functions is not derived in the calculus but adopted as a principle of the calculus. In this paper, we propose a simple symmetric lambda-calculus corresponding to the negation-free natural deduction based bilateralism in proof-theoretic semantics. In our calculus, continuation types are represented as not negations of formulae but formulae with negative polarity. Function types are represented as the implication and but-not connectives in intuitionistic and paraconsistent logics, respectively. Our calculus is not only simple but also powerful as it includes a call-value calculus corresponding to the call-by-value dual calculus invented by Wadler. We show that mutual transformations between expressions and continuations are definable in our calculus to justify the duality of functions. We also show that every typable function has dual types. Thus, the duality of function is derived from bilateralism. 2012 ACM Subject Classification Theory of computation → Logic; Theory of computation → Type theory Keywords and phrases symmetric lambda-calculus, formulae-as-types, duality, bilateralism, natural deduction, proof-theoretic semantics, but-not connective, continuation, call-by-value Acknowledgements The author thanks Yosuke Fukuda, Tasuku Hiraishi, Kentaro Kikuchi, and Takeshi Tsukada for the fruitful discussions, which clarified contributions of the present paper. -
Journal of Linguistics Negation, 'Presupposition'
Journal of Linguistics http://journals.cambridge.org/LIN Additional services for Journal of Linguistics: Email alerts: Click here Subscriptions: Click here Commercial reprints: Click here Terms of use : Click here Negation, ‘presupposition’ and the semantics/pragmatics distinction ROBYN CARSTON Journal of Linguistics / Volume 34 / Issue 02 / September 1998, pp 309 350 DOI: null, Published online: 08 September 2000 Link to this article: http://journals.cambridge.org/abstract_S0022226798007063 How to cite this article: ROBYN CARSTON (1998). Negation, ‘presupposition’ and the semantics/pragmatics distinction. Journal of Linguistics, 34, pp 309350 Request Permissions : Click here Downloaded from http://journals.cambridge.org/LIN, IP address: 144.82.107.34 on 12 Oct 2012 J. Linguistics (), –. Printed in the United Kingdom # Cambridge University Press Negation, ‘presupposition’ and the semantics/pragmatics distinction1 ROBYN CARSTON Department of Phonetics and Linguistics, University College London (Received February ; revised April ) A cognitive pragmatic approach is taken to some long-standing problem cases of negation, the so-called presupposition denial cases. It is argued that a full account of the processes and levels of representation involved in their interpretation typically requires the sequential pragmatic derivation of two different propositions expressed. The first is one in which the presupposition is preserved and, following the rejection of this, the second involves the echoic (metalinguistic) use of material falling in the scope of the negation. The semantic base for these processes is the standard anti- presuppositionalist wide-scope negation. A different view, developed by Burton- Roberts (a, b), takes presupposition to be a semantic relation encoded in natural language and so argues for a negation operator that does not cancel presuppositions. -
Expressing Negation
Expressing Negation William A. Ladusaw University of California, Santa Cruz Introduction* My focus in this paper is the syntax-semantics interface for the interpretation of negation in languages which show negative concord, as illustrated in the sentences in (1)-(4). (1) Nobody said nothing to nobody. [NS English] ‘Nobody said anything to anyone.’ (2) Maria didn’t say nothing to nobody. [NS English] ‘Maria didn’t say anything to anyone.’ (3) Mario non ha parlato di niente con nessuno. [Italian] ‘Mario hasn’t spoken with anyone about anything.’ (4) No m’ha telefonat ningú. [Catalan] ‘Nobody has telephoned me.’ Negative concord (NC) is the indication at multiple points in a clause of the fact that the clause is to be interpreted as semantically negated. In a widely spoken and even more widely understood nonstandard dialect of English, sentences (1) and (2) are interpreted as synonymous with those given as glosses, which are also well-formed in the dialect. The examples in (3) from Italian and (4) from Catalan illustrate the same phenomenon. The occurrence in these sentences of two or three different words, any one of which when correctly positioned would be sufficient to negate a clause, does not guarantee that their interpretation involves two or three independent expressions of negation. These clauses express only one negation, which is, on one view, simply redundantly indicated in two or three different places; each of the italicized terms in these sentences might be seen as having an equal claim to the function of expressing negation. However closer inspection indicates that this is not the correct view. -
Basic Category Theory and Topos Theory
Basic Category Theory and Topos Theory Jaap van Oosten Jaap van Oosten Department of Mathematics Utrecht University The Netherlands Revised, February 2016 Contents 1 Categories and Functors 1 1.1 Definitions and examples . 1 1.2 Some special objects and arrows . 5 2 Natural transformations 8 2.1 The Yoneda lemma . 8 2.2 Examples of natural transformations . 11 2.3 Equivalence of categories; an example . 13 3 (Co)cones and (Co)limits 16 3.1 Limits . 16 3.2 Limits by products and equalizers . 23 3.3 Complete Categories . 24 3.4 Colimits . 25 4 A little piece of categorical logic 28 4.1 Regular categories and subobjects . 28 4.2 The logic of regular categories . 34 4.3 The language L(C) and theory T (C) associated to a regular cat- egory C ................................ 39 4.4 The category C(T ) associated to a theory T : Completeness Theorem 41 4.5 Example of a regular category . 44 5 Adjunctions 47 5.1 Adjoint functors . 47 5.2 Expressing (co)completeness by existence of adjoints; preserva- tion of (co)limits by adjoint functors . 52 6 Monads and Algebras 56 6.1 Algebras for a monad . 57 6.2 T -Algebras at least as complete as D . 61 6.3 The Kleisli category of a monad . 62 7 Cartesian closed categories and the λ-calculus 64 7.1 Cartesian closed categories (ccc's); examples and basic facts . 64 7.2 Typed λ-calculus and cartesian closed categories . 68 7.3 Representation of primitive recursive functions in ccc's with nat- ural numbers object . -
Distribution Algebras and Duality
Advances in Mathematics 156, 133155 (2000) doi:10.1006Âaima.2000.1947, available online at http:ÂÂwww.idealibrary.com on Distribution Algebras and Duality Marta Bunge Department of Mathematics and Statistics, McGill University, 805 Sherbrooke Street West, Montreal, Quebec, Canada H3A 2K6 Jonathon Funk Department of Mathematics, University of Saskatchewan, 106 Wiggins Road, Saskatoon, Saskatchewan, Canada S7N 5E6 Mamuka Jibladze CORE Metadata, citation and similar papers at core.ac.uk Provided by ElsevierDepartement - Publisher Connector de Mathematique , Louvain-la-Neuve, Chemin du Cyclotron 2, 1348 Louvain-la-Neuve, Belgium; and Institute of Mathematics, Georgian Academy of Sciences, M. Alexidze Street 1, Tbilisi 380093, Republic of Georgia and Thomas Streicher Fachbereich 4 Mathematik, TU Darmstadt, Schlo;gartenstrasse 7, 64289 Darmstadt, Germany Communicated by Ross Street Received May 20, 2000; accepted May 20, 2000 0. INTRODUCTION Since being introduced by F. W. Lawvere in 1983, considerable progress has been made in the study of distributions on toposes from a variety of viewpoints [59, 12, 15, 19, 24]. However, much work still remains to be done in this area. The purpose of this paper is to deepen our understanding of topos distributions by exploring a (dual) lattice-theoretic notion of dis- tribution algebra. We characterize the distribution algebras in E relative to S as the S-bicomplete S-atomic Heyting algebras in E. As an illustration, we employ distribution algebras explicitly in order to give an alternative description of the display locale (complete spread) of a distribution [7, 10, 12]. 133 0001-8708Â00 35.00 Copyright 2000 by Academic Press All rights of reproduction in any form reserved. -
A Descriptive Study of California Continuation High Schools
Issue Brief April 2008 Alternative Education Options: A Descriptive Study of California Continuation High Schools Jorge Ruiz de Velasco, Greg Austin, Don Dixon, Joseph Johnson, Milbrey McLaughlin, & Lynne Perez Continuation high schools and the students they serve are largely invisible to most Californians. Yet, state school authorities estimate This issue brief summarizes that over 115,000 California high school students will pass through one initial findings from a year- of the state’s 519 continuation high schools each year, either on their long descriptive study of way to a diploma, or to dropping out of school altogether (Austin & continuation high schools in 1 California. It is the first in a Dixon, 2008). Since 1965, state law has mandated that most school series of reports from the on- districts enrolling over 100 12th grade students make available a going California Alternative continuation program or school that provides an alternative route to Education Research Project the high school diploma for youth vulnerable to academic or conducted jointly by the John behavioral failure. The law provides for the creation of continuation W. Gardner Center at Stanford University, the schools ‚designed to meet the educational needs of each pupil, National Center for Urban including, but not limited to, independent study, regional occupation School Transformation at San programs, work study, career counseling, and job placement services.‛ Diego State University, and It contemplates more intensive services and accelerated credit accrual WestEd. strategies so that students whose achievement in comprehensive schools has lagged might have a renewed opportunity to ‚complete the This project was made required academic courses of instruction to graduate from high school.‛ 2 possible by a generous grant from the James Irvine Taken together, the size, scope and legislative design of the Foundation. -
Logic, Sets, and Proofs David A
Logic, Sets, and Proofs David A. Cox and Catherine C. McGeoch Amherst College 1 Logic Logical Statements. A logical statement is a mathematical statement that is either true or false. Here we denote logical statements with capital letters A; B. Logical statements be combined to form new logical statements as follows: Name Notation Conjunction A and B Disjunction A or B Negation not A :A Implication A implies B if A, then B A ) B Equivalence A if and only if B A , B Here are some examples of conjunction, disjunction and negation: x > 1 and x < 3: This is true when x is in the open interval (1; 3). x > 1 or x < 3: This is true for all real numbers x. :(x > 1): This is the same as x ≤ 1. Here are two logical statements that are true: x > 4 ) x > 2. x2 = 1 , (x = 1 or x = −1). Note that \x = 1 or x = −1" is usually written x = ±1. Converses, Contrapositives, and Tautologies. We begin with converses and contrapositives: • The converse of \A implies B" is \B implies A". • The contrapositive of \A implies B" is \:B implies :A" Thus the statement \x > 4 ) x > 2" has: • Converse: x > 2 ) x > 4. • Contrapositive: x ≤ 2 ) x ≤ 4. 1 Some logical statements are guaranteed to always be true. These are tautologies. Here are two tautologies that involve converses and contrapositives: • (A if and only if B) , ((A implies B) and (B implies A)). In other words, A and B are equivalent exactly when both A ) B and its converse are true. -
RELATIONAL PARAMETRICITY and CONTROL 1. Introduction the Λ
Logical Methods in Computer Science Vol. 2 (3:3) 2006, pp. 1–22 Submitted Dec. 16, 2005 www.lmcs-online.org Published Jul. 27, 2006 RELATIONAL PARAMETRICITY AND CONTROL MASAHITO HASEGAWA Research Institute for Mathematical Sciences, Kyoto University, Kyoto 606-8502 Japan, and PRESTO, Japan Science and Technology Agency e-mail address: [email protected] Abstract. We study the equational theory of Parigot’s second-order λµ-calculus in con- nection with a call-by-name continuation-passing style (CPS) translation into a fragment of the second-order λ-calculus. It is observed that the relational parametricity on the tar- get calculus induces a natural notion of equivalence on the λµ-terms. On the other hand, the unconstrained relational parametricity on the λµ-calculus turns out to be inconsis- tent. Following these facts, we propose to formulate the relational parametricity on the λµ-calculus in a constrained way, which might be called “focal parametricity”. Dedicated to Prof. Gordon Plotkin on the occasion of his sixtieth birthday 1. Introduction The λµ-calculus, introduced by Parigot [26], has been one of the representative term calculi for classical natural deduction, and widely studied from various aspects. Although it still is an active research subject, it can be said that we have some reasonable un- derstanding of the first-order propositional λµ-calculus: we have good reduction theories, well-established CPS semantics and the corresponding operational semantics, and also some canonical equational theories enjoying semantic completeness [16, 24, 25, 36, 39]. The last point cannot be overlooked, as such complete axiomatizations provide deep understand- ing of equivalences between proofs and also of the semantic structure behind the syntactic presentation.