this paper we examine the connection between two areas of semantics, namely the semantics of historical databases and the semantics of natural language querying, and link them together via a common view of the semantics of time. Since the target application domain is an historical database, we present the essential features of the Historical Relational Database Model (HRDM), an extension to the relational model motivated by the desire to incorporate more "real world" semantics into a database at the conceptual level. We then present the essential features of QE-III, a formally defined English database query language whose semantic and pragmatic theory, based on a Montague-type semantics, makes explicit reference to the notion of denotation with respect to a moment of time. We demonstrate the use of this language to query an example historical database, and discuss the issues of how to provide both a semantic and a pragmatic interpretation for questions within a model-theoretic framework

Semantic Networks (SN) have been used in many applications, especially in the field of natural language understanding (NLU). The multilayered extended semantic network MESNET presented in this paper on the one hand follows the tradition of semantic networks (SN) starting with the work of Quillian (13). On the other hand, MESNET for the first time consequently and explicitly makes use of a multilayered structuring of a SN built upon an orthogonal system of dimensions and especially upon the distinction between an intensional and a preextensional layer. Furthermore, MESNET is based on a comprehensive system of classificatory means (sorts and features) as well as on semantically primitive relations and functions. It uses a relatively large but fixed inventory of representational means, encapsulation of concepts and a distinction between immanent and situative knowledge. The whole complex of representational means is independent of special application domains. With regard to the representa...

We show that a 0-1 law holds for propositional modal logic, both for structure validity and frame validity. In the case of structure validity, the result follows easily from the wellknown 0-1 law for first-order logic. However, our proof gives considerably more information. It leads to an elegant axiomatization for almost-sure structure validity and to sharper complexity bounds. Since frame validity can be reduced to a \Pi 1 1 formula, the 0-1 law for frame validity helps delineate when 0-1 laws exist for second-order logics. A preliminary version of this paper appears in Proceedings of the Seventh Annual IEEE Symposium on Logic in Computer Science, 1992. This version is almost identical to one that appears in a special issue of Annals of Pure and Applied Logic (vol. 69, 1994, pp. 157--193) devoted to the papers of this conference. y Part of the work of the first author was performed while he was on sabbatical at the University of Toronto. z The work of the second author was com...

Lexicon coverage is often the limiting factor in natural language processing systems. Recent work has attempted to remedy this situation by extracting information from machine readable dictionaries. Unfortunately, no NLP lexicon system or dictionary could possibly list all the potential words of English. However, humans are often able to interpret novel word forms (that is, words they have not seen before) without difficulty. One way we do this, if the word is complex (e.g. undecidability), is by using cues from the internal structure of the word. Relations in phonological form often correspond to relations in meaning. For example, if someone knows what the verb open means, a number of educated guesses can be made about the meaning of reopen. Exceptions abound in lexical data and any system that attempts to use lexical generalizations must be able to handle exceptions in a principled fashion. In this report, I will describe the preliminary design of a system that uses relations in form...

Many tools have been developed to date that employ intensionalized identifiers, markup, or files to accomplish versioning; however, most of these tools have been localized in utility. Packages such as Lemur and IHTML have effectively applied versioning to specific systems (in the case of Lemur and IHTML, to C projects and HTML files, respectively) but were not generally applicable to projects and source-files in other programming environments. In this thesis, I will present some general tools and languages that can be used to version arbitrary projects in a structured fashion. Vmake is a make tool, similar in design to traditional make programs, but which operates on versioned source-files of arbitrary types, and which allows the target-names and dependencies of each rule to be versioned. That is to say, just as every file can exist in multiple versions, so too can each of the rules in the makefile. At every level of the resulting make tree, an intensional best-fit is made on each of the targets for a given rule, to determine which rule or file will be used for the target. Because the rule names and file names in a make program are the true identifiers of the program, Vmake can be thought of as a general, intensional, rulebased build-language. It can be used to apply versioning to any software entity that can be constructed from source files and/or shell commands. ISE, for "Intensional Sequential Evaluator", is an imperative scripting language written in the spirit of Perl, but which uses versioning for all of its identifiers, including variables, files and functions. The language has most of the flow-control and data structures of Perl and C, but allows each construct to be versioned. The basic idea of ISE is that a thread of execution carries with it a current context (or global ...

By the theory TT is meant the higher order predicate logic with the following recursively defined types: (1) 1 is the type ofindividuals and [] is the type ofthe truth values; (2) [# 1 ,..., n ] is the type ofthe predicates with arguments ofthe types #1 ,...,# n . The theory ITT described in this paper is an intensional version ofTT. The types ofITT are the same as the types ofTT, but the membership ofthe type 1 ofindividuals in ITT is an extension ofthe membership in TT. The extension consists ofallowing any higher order term, in which only variables oftype 1 have a free occurrence, to be a term oftype 1. This feature ofITT is motivated by a nominalist interpretation ofhigher order predication. In ITT both well-founded and non-well-founded recursive predicates can be defined as abstraction terms from which all the properties of the predicates can be derived without the use ofnon-logical axioms. The elementary syntax, semantics, and prooftheory for ITT are defined. A semantic consistency prooffor ITT is provided and the completeness proofofTakahashi and Prawitz for a version of TT without cut is adapted for ITT; a consequence is the redundancy of cut. 1.

In this essay I will consider two theses that are associated with Frege, and will investigate the extent to which Frege “really ” believed them. Much of what I have to say will come as no surprise to scholars of the historical Frege. But Frege is not only a historical figure; he also occupies a site on the philosophical landscape that has allowed his doctrines to seep into the subconscious water table. And scholars in a wide variety of different scholarly establishments then sip from these doctrines. I believe that some Frege-interested philosophers at various of these establishments might find my conclusions surprising. Some of these philosophical establishments have arisen from an educational milieu in which Frege is associated with some specific doctrine at the expense of not even being aware of other milieux where other specific doctrines are given sole prominence. The two theses which I will discuss illustrate this point: Each of them is called “Frege’s Principle”, but by philosophers from different milieux. By calling them ‘milieux ’ I do not want to convey the idea that they are each located at some specific socio-politico-geographico-temporal location. Rather, it is a matter of their each being located at different places on the intellectual landscape. For this reason one might (and I sometimes will) call them “(interpretive) traditions.”

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this paper. The assorted data thus far adduced provide strong support for the desirability of an account satisfying C1-C4 and show at least that any semantics not satisfying C1-C4 leaves much unexplained.

The paper argues that Guarino is right that ontologies are different from thesauri and similar objects, but not in the ways he believes: they are distinguished from essentially linguistic objects like thesauri and hierarchies of conceptual relations because they unpack, ultimately, in terms of sets of objects and individuals. However this is a lonely status, and without much application outside strict scientific and engineering disciplines, and of no direct relevance to language processing (NLP). More interesting structures, of NLP relevance, that encode conceptual knowledge, cannot be subjected to the “cleaning up ” techniques that Guarino advocates, because his conditions are too strict to be applicable, and because the terms used in such structures retain their language-like features of ambiguity and vagueness, and in a way that cannot be eliminated by reference to sets of objects, as it can be in ontologies in the narrow sense. Wordnet is a structure that remains useful to NLP, and has within it features of both types (ontologies and conceptual hierarchies) and its function and usefulness will remain, properly, resistant to Guarino’s techniques, because those rest on a misunderstanding about concepts. The ultimate way out of such disputes can only come from automatic construction and evaluation procedures for conceptual and ontological structures from data, which is to say, corpora. Key words: ontologies, thesauri, necessary and sufficient conditions, identity criteria, evaluation.