Theo Janssen

Bio: Theo Janssen is an academic researcher from University of Amsterdam. The author has contributed to research in topics: Natural language & Formal semantics (linguistics). The author has an hindex of 13, co-authored 55 publications receiving 1186 citations. Previous affiliations of Theo Janssen include VU University Amsterdam.

Chapter 7 – Compositionality

Abstract: Publisher Summary This chapter provides a precise interpretation of the principle of compositionality and a mathematical model for the principle. The principle of compositionality is a restriction that rules out several proposals in the literature, and is certainly not vacuous. On the other hand, it shows that there are several methods to obtain a compositional meaning assignment; so it is not an impossible task. Compositionality is not a formal restriction on what can be achieved, but a methodology on how to proceed. The discussions in this chapter have pointed to several advantages of this methodology, in particular its heuristic value. It suggests solutions to semantic problems. It helps to find weak spots in non-compositional proposals; such proposals have a risk of being defective. Cases where an initially noncompositional proposal was turned into a compositional one, the analysis is improved considerably. Compositionality requires a decision on what in a given approach the basic semantic units are: if one has to build meanings from them, it has to be decided what these units are. Compositionality also requires a decision on what the basic units in syntax are, and how they are combined.

Frege, Contextuality and Compositionality

Abstract: There are two principles which bear the name “Frege's principle:” the principle of compositionality, and the context principle. The aim of this contribution is to investigate whether this is justified: did Frege accept both principles at the same time, did he hold the one principle but not the other, or did he, at some moment, change his opinion? The conclusion is as follows. There is a development in Frege's position. In the period of Grundlagen he followed to a strict form of contextuality. He repeated contextuality in later writings, but became less strict. From 1914 on, pushed by the needs of research, he comes close to compositionality. But he could never make the final step toward compositionality for principled reasons, therefore he always would reject compositionality.

Equivalence and quantifier rules for logic with imperfect information

Abstract: In this paper, we present a prenex form theorem for a version of Independence Friendly logic, a logic with imperfect information. Lifting classical results to such logics turns out not to be straightforward, because independence conditions make the formulas sensitive to signalling phenomena. In particular, nested quantification over the same variable is shown to cause problems. For instance, renaming of bound variables may change the interpretations of a formula, there are only restricted quantifier extraction theorems, and slashed connectives cannot be so easily removed. Thus we correct some claims from Hintikka [8], Caicedo & Krynicki [3] and Hodges [11]. We refine definitions, in particular the notion of equivalence, and sharpen preconditions, allowing us to restore (restricted versions of) those claims, including the prenex form theorem of Caicedo & Krynicki [3], and, as a side result, we obtain an application to Skolem forms of classical formulas. It is a known fact that a complete calculus for IF-logic is impossible, but with our results we establish several quantifier rules that form a partial calculus of equivalence for a general version of IF-logic reflecting general properties of information flow in games.

打磨Using Language,倡导新理念

Abstract: 人教版高中英语新课程教材中,语言运用（Using Language）是每个单元必不可少的部分,提供了围绕单元中心话题的听、说、读、写的综合性练习,是单元中心话题的延续和升华.如何设计Using Language部分的教学,使自己的教学模式既不落俗套,又能真正体现新课程标准所倡导的教学理念,正是广大一线英语教师一直努力探索的问题.

From Discourse to Logic : Introduction to Modeltheoretic Semantics of Natural Language Formal Logic and Discourse Representation Theory

Abstract: Preface. 0: Preliminaries. 0.1. Theories of Meaning. 0.2. Logic. 0.3. Logic and Semantics. 0.4. Syntax. 1: DRT and Predicate Logic. 1.1. Simple Sentences. 1.2. Models. 1.3. Negation. 1.4. Verification, Truth and Accessibility. 1.5. From DRT to Predicate Logic. 2: Quantification and Connectives. 2.1. Conditionals. 2.2. Universal Quantification. 2.3. Disjunction. 2.4. Conjunction. 3: Loose Ends. 3.1. Reflexives. 3.2. Possessive Noun Phrases. 3.3. Proper Names. 3.4. Definite Descriptions. 3.5. Stipulated Identity and Asserted Identity. 3.6. Identity and Predication. 3.7. Scope Amibiguity. 4: The Plural. 4.1. Introduction. 4.2. DRS-Construction for Plurals I. 4.3. Model Theory. 4.4. DRS-Construction for Plurals II. 5: Tense and Aspect. 5.1. The Semantics and Logic of Temporal Reference. 5.2. DRS-Construction for Tensed Sentences. 5.3. Aspect. 5.4. Temporal Perspective. 5.5. Temporal Adverbials. 5.6. Model Theory. 5.7. Syntactic Rules. Bibliography. Table of Construction Rules. Index of Symbols, Features and Feature Values. Index of Names. Index of Subjects.

Identificational focus versus information focus

Abstract: feature specification of identificational focus is shown to be subject to parametric variation: the focus operators of various languages are specified for the positive value of either or both of the features [+exhaustive] and [+contrastive].* I will put forth two major claims in this article: first, that IDENTIFICATIONAL FOCUS (sometimes also called contrastive focus) has to be consistently distinguished from a mere INFORMATION FOCUS (or presentational focus), as it has syntactic and semantic properties that a mere information focus does not share. Second, I will show that the identificational focus itself is not uniform across languages; it is associated with different subsets of a set of semantic features. Identificational focus and information focus are often mingled in language description, which leads to contradictory statements on focus. I identify the syntactic and semantic properties of identificational focus on the basis of Hungarian and English material, and argue that English, like Hungarian, is a language with visible identificational focus movement. The identificational focus is realized as a cleft constituent. I then discuss a special type of identificational focus: the only-phrase, and finally I compare the feature content of the identificational focus of Hungarian and English with the feature contents of its Italian, Rumanian, Catalan, Greek, Arabic, and Finnish counterparts. 1. A NEGLECTED DISTINCTION. The claim that two different types of focus can be distinguished-one expressing a quantification-like operation, and another merely conveying nonpresupposed information-has been present in the linguistic literature for a long time (see, for example, Halliday 1967 and Rochemont 1986), although the interpretations attributed to the two focus notions (variously called CONTRASTIVE FOCUS versus PRESENTATIONAL FOCUS, NARROW FOCUS versus WIDE FOCUS, or in this article, IDENTIFICATIONAL FOCUS versus INFORMATION FOCUS) have not always been exactly the same.