“It’s so hard to be a saint in the city,” sings Bruce Springsteen in a ballad released 35 years ago. Judging from the national popular sentiment about the matter, he could have been talking about the complexity of being a philosopher in Turkey.

Analogy-making is finding analogies between different situations. In this paper, we provide a new model of computational analogy-making which uses Situation Theory as its formal background. Situation Theory is a semantic and logical theory which provides a naturalistic way to represent relations in situations. The system described in this paper is aimed at solving analogy problems made by basic geometric figures in a chessboard-like environment.

In this paper we attempt to develop a problem representation technique which enables the decomposition of a problem into subproblems such that their solution in sequence constitutes a strategy for solving the problem. An important issue here is that the subproblems generated should be easier than the main problem. We propose to represent a set of problem states by a statement which is true for all the members of the set. A statement itself is just a set of atomic statements (...) which are binary predicates on state variables. Then, the statement representing the set of goal states can be partitioned into its subsets each of which becomes a subgoal of the resulting strategy. The techniques involved in partitioning a goal into its subgoals are presented with examples. (shrink)

Some recent studies in computational linguistics have aimed to take advantage of various cues presented by punctuation marks. This short survey is intended to summarise these research efforts and additionally, to outline a current perspective for the usage and functions of punctuation marks. We conclude by presenting an information-based framework for punctuation, influenced by treatments of several related phenomena in computational linguistics.

The issue of context arises in assorted areas of Artificial Intelligence. Although its importance is realized by various researchers, there is not much work towards a useful formalization. In this paper, we will present a preliminary model (based on Situation Theory) and give examples to show the use of context in various fields, and the advantages gained by the acceptance of our proposal.

This is the proceedings of the "1st Turkish Conference on AI and ANNs," K. Oflazer, V. Akman, H. A. Guvenir, and U. Halici (editors). The conference was held at Bilkent University, Bilkent, Ankara on 25-26 June 1992. -/- Language of contributions: English and Turkish.

The papers that make up this special issue do not take idealized abstractions of context as their point of departure but rather start with the actual phenomena under study and later generalize. We agree that, more often than not, giving a formal model and providing a theory of a loaded notion – such as context – can lead to important insights. Thus, precise models of context and accompanying theories are useful. However, given the widely different fields, methodologies and worldviews within (...) which people study, an approach that starts with the root phenomena/problems and only attempts normalization and generalization post hoc might be a more productive way to proceed. (shrink)

Anaphora resolution is one of the most active research areas in natural language processing. This study examines focusing as a tool for the resolution of pronouns which are a kind of anaphora. Focusing is a discourse phenomenon like anaphora. Candy Sidner formalized focusing in her 1979 MIT PhD thesis and devised several algorithms to resolve definite anaphora including pronouns. She presented her theory in a computational framework but did not generally implement the algorithms. Her algorithms related to focusing and pronoun (...) resolution are implemented in this paper. This implementation provides a better comprehension of the theory both from a conceptual and a computational point of view. The resulting program is tested on different discourse segments, and evaluation and analysis of the experiments are presented together with the statistical results. (shrink)

The success of set theory as a foundation for mathematics inspires its use in artificial intelligence, particularly in commonsense reasoning. In this survey, we briefly review classical set theory from an AI perspective, and then consider alternative set theories. Desirable properties of a possible commonsense set theory are investigated, treating different aspects like cumulative hierarchy, self-reference, cardinality, etc. Assorted examples from the ground-breaking research on the subject are also given.

This paper investigates an alternative set theory (due to Peter Aczel) called Hyperset Theory. Aczel uses a graphical representation for sets and thereby allows the representation of non-well-founded sets. A program, called HYPERSOLVER, which can solve systems of equations defined in terms of sets in the universe of this new theory is presented. This may be a useful tool for commonsense reasoning.

The work described in this report is motivated by the desire to test the expressive possibilities of action language C+. The Causal Calculator (CCalc) is a system that answers queries about action domains described in a fragment of that language. The Zoo World and the Traffic World have been proposed by Erik Sandewall in his Logic Modelling Workshop—an environment for communicating axiomatizations of action domains of nontrivial size. -/- The Zoo World consists of several cages and the exterior, gates between (...) them, and animals of several species, including humans. Actions in this domain include moving within and between cages, opening and closing gates, and mounting and riding animals. The Traffic World includes vehicles moving continuously between road crossings subject to a number of restrictions, such as speed limits and keeping a fixed safety distance away from other vehicles on the road. We show how to represent the two domains in the input language of CCalc, and how to use CCalc to test these representations. (shrink)

The importance of contextual reasoning is emphasized by various researchers in AI. (A partial list includes John McCarthy and his group, R. V. Guha, Yoav Shoham, Giuseppe Attardi and Maria Simi, and Fausto Giunchiglia and his group.) Here, we survey the problem of formalizing context and explore what is needed for an acceptable account of this abstract notion.

The Turing Test is one of the most disputed topics in artificial intelligence, philosophy of mind, and cognitive science. This paper is a review of the past 50 years of the Turing Test. Philosophical debates, practical developments and repercussions in related disciplines are all covered. We discuss Turing's ideas in detail and present the important comments that have been made on them. Within this context, behaviorism, consciousness, the 'other minds' problem, and similar topics in philosophy of mind are discussed. We (...) also cover the sociological and psychological aspects of the Turing Test. Finally, we look at the current situation and analyze programs that have been developed with the aim of passing the Turing Test. We conclude that the Turing Test has been, and will continue to be, an influential and controversial topic. -/- (This paper was reprinted in: The Turing Test: The Elusive Standard of Artificial Intelligence, J. H. Moor, ed., Kluwer Academic, pp. 23-78, 2003.). (shrink)

Papers in this special issue were written upon invitation. They were then subjected to the usual refereeing process of the Journal of Pragmatics. While we have attempted to cover almost all important areas in which context is employed as a conceptual apparatus, our coverage is clearly limited in scope. Accordingly, instead of a general updated overview of the use of context in every conceivable specific field (let's say the state-of-the-art of interdisciplinary research on context: a colossal/impossible enterprise!), we will offer (...) the readers of this special issue an introduction to the problems involved in the study of context by way of eight papers encompassing eight different areas. These are (in alphabetical order): artificial intelligence, bilingualism, child development, cognitive science, conversation analysis, neuroscience, philosophy of language, and pragmatics. Our goal is to propose a multi-faceted view of context, and to stimulate further investigations of this fertile topic, which permeates our lives. (shrink)

The standard propositional exposition of necessary and sufficient conditions, as available in introductory logic texts, leads to a contradiction. It should be abolished.

At the heart of natural language processing is the understanding of context dependent meanings. This paper presents a preliminary model of formal contexts based on situation theory. It also gives a worked-out example to show the use of contexts in lifting, i.e., how propositions holding in a particular context transform when they are moved to another context. This is useful in NLP applications where preserving meaning is a desideratum.

Strawson proposed in the early seventies an attractive threefold distinction regarding how context bears on the meaning of 'what is said' when a sentence is uttered. The proposed scheme is somewhat crude and, being aware of this aspect, Strawson himself raised various points to make it more adequate. In this paper, we review the scheme of Strawson, note his concerns, and add some of our own. However, our main point is to defend the essence of Strawson's approach and to recommend (...) it as a starting point for research into intended meaning and context. (shrink)

Bilkent Üniversitesi'nde bu yıl [2003] açılan Felsefe Bölümü’nün başkanlığını yürüten ve ana ilgi alanı yapay zekâ olan Prof. Dr. Varol Akman, yapay zekâyla felsefenin ilişkisini ve Felsefe Bölümü'nün özelliklerini anlattı. (An interview published in Bilkent Magazine about the then new Bilkent Philosophy Department.).

This paper argues that in addition to the familiar approach using formal contexts, there is now a need in artificial intelligence to study contexts as social constructs. As a successful example of the latter approach, I draw attention to 'interpretation' (in the sense of literary theory), viz. the reconstruction of the intended meaning of a literary text that takes into account the context in which the author assumed the reader would place the text. An important contribution here comes from Wendell (...) Harris, enumerating the seven crucial dimensions of context: knowledge of reality, knowledge of language, and the authorial, generic, collective, specific, and textual dimensions. Finally, two recent approaches to interpretation, due to Jon Barwise and Jerry Hobbs, are analyzed as useful attempts which also come to grips with the notion of context. It must be noted that there has been a considerable body of contributions connecting linguistic structure with social context. For example, anthropological linguistics, from Bronislaw Malinowski onwards, has underlined the cultural context of discourse as essential to meaning. This viewpoint became prominent with the emergence of the ethnography of speaking in anthropology. Thus, conversation analysis represents a consistent formal effort to contribute to an analysis of the nature of context. While this paper emphasizes and reviews the literary theory approach, it makes various contacts with works of the latter kind (e.g., the landmark contributions of Erving Goffman, John Gumperz, William Hanks, John Heritage, Dell Hymes, et al.) in order to deliver a more balanced and complete study of the dimensions of context. (shrink)

Situated semantics can be regarded as an attempt at placing situational context (context of situation) at the center of all discussions of meaning. Situation theory is a theory of information content that takes context very seriously. Individuals, properties, relations, and spatiotemporal locations are basic constructs of situation theory. Individuals are conceived as invariants; having properties and standing in relations, they tend to persist in time and space. An anchoring function binds the location parameters to appropriate objects present in the grounding (...) situation. Anchoring plays a major role in the working of constraints that include nomic constraints, conventional constraints and conditional constraints. Situation semantics develops a theory of meaning that is based on relations between situations. Situation semantics provides a fundamental framework for realistic semantics. The ideas emerging from research into situation semantics have been combined with linguistic work and have led to numerous useful proposals. (shrink)

Commonsense reasoning about the physical world, as exemplified by "Iron sinks in water" or "If a ball is dropped it gains speed," will be indispensable in future programs. We argue that to make such predictions (namely, envisioning), programs should use abstract entities (such as the gravitational field), principles (such as the principle of superposition), and laws (such as the conservation of energy) of physics for representation and reasoning. These arguments are in accord with a recent study in physics instruction where (...) expert problem solving is related to the construction of physical representations that contain fictitious, imagined entities such as forces and momenta (Larkin 1983). We give several examples showing the power of physical representations. (shrink)

An information-based approach to natural language semantics. Formulated by Jon Barwise and John Perry in their influential book Situations and Attitudes (1983), it is built upon the notion of a 'situation' --- a limited part of the real world that a cognitive agent can individuate and has access to. A situation represents a lump of information in terms of a collection of facts. It is through the actualist ontology of situations that the meaning of natural language utterances can be elucidated.

Logical connectives (otherwise known as 'logical constants' or 'logical particles') have seemed challenging to philosophers of language. This article gives a concise account of logical connectives.

In a paper published in 1992, Dennis Kurzon shows that silence does not necessarily mean lack of power: the silent response to a question may well be aiming at gaining control of a situation, viz. exercising power. I would like to extend Kurzon's analysis and argue that at times silence may mean derision or ridicule.

Vagueness, 'the quality or condition of being vague' (OED), has kept philosophers busy since ancient times. This article gives a concise account of vagueness.

Future robots should have common sense about the world in order to handle the problems they will encounter. A large part of this commonsense knowledge must be naive physics knowledge, since carrying out even the simplest everyday chores requires familiarity with physics laws. But how should one start codifying this knowledge? What kind of skills should be elicited from the experts (each and every one of us)? This paper will attempt to provide some hints by studying the mental models of (...) force and motion. (shrink)

A logical formalization of emotions is considered to be tricky because they appear to have no strict types, reasons, and consequences. On the other hand, such a formalization is crucial for commonsense reasoning. Here, the so-called "object directedness" of emotions is studied by using Helen Nissenbaum's influential ideas.

This article first appeared in "Encyclopedia of Language and Linguistics 2nd Edition," Keith Brown, ed., pp. 398-401, Elsevier, Amsterdam, 2006.

Having been influenced by John Perry's 1997 article, "Indexicals and Demonstratives," in this paper I take a closer look at contexts for indexicals, more specifically the indexical "I." (N.B. The adjective in the title is not misspelt; it is used in the sense of the leading brand of premium vodka.).

Planlama --- bir amaca ulaşmak üzere bir aksiyonlar bütünü tasarlamak --- yapay zekadaki en temel problemlerden biridir. Bu yazıda, robotikte planlama konusuna mantıkçı (logicist) yaklaşım ele alınmaktadır. [Planning --- devising a plan of action to reach a given goal --- is a fundamental problem in AI. This paper reviews the logicist approach to planning in robotics.].

John Perry argued that the clearest case of an indexical that relies only on the narrow context is 'I,' whose designation depends on the agent and nothing else. In this presentation, I give some examples which show that this view, while essentially correct, may have problems in some rare divergent cases.

In Strawson’s Entity and Identity, there are two essays (Chapters 11 and 12), which study the notion of context. In these essays, Strawson advances a threefold distinction regarding how context bears on the meaning of 'what is said' when a sentence is uttered. -/- In this paper, we'll (i) review the original scheme of Strawson and summarize his improvements to his own scheme, and (ii) add our own improvements to make it even more thoroughgoing. We'll also show that unless it (...) is elaborated with several considerations (mostly based on our work regarding context as a social construct and contextualizing as a form of social action) it cannot function as a realistic initiative towards building common sense models of how intended meaning is achieved. (shrink)

This is a short piece of humor (I hope) on nonstandard set theories. An earlier version appeared in Bull. EATCS 45: 146-147 (1991).

We describe an experimental approach toward implementing a commonsense "microtheory" for buying and selling. Our prototype system characterizes how intelligent agents hold items and money, how they buy and sell items, and the way money and items are transferred. The ontology of the system includes money (cash, check, credit card), agents (people, organizations), items (movable, real estate, service), barter, and the notions of transfer, loan, buying by installments, profit, and loss.

In logic, the law (or principle) of identity states simply: 'A is A'. This article gives a concise account of identity.

We consider an objection of Hans Kamp (based on an example by Barbara Partee) to Robert Stalnaker's model of context.

The merits of set theory as a foundational tool in mathematics stimulate its use in various areas of artificial intelligence, in particular intelligent information systems. In this paper, a study of various nonstandard treatments of set theory from this perspective is offered. Applications of these alternative set theories to information or knowledge management are surveyed.

The papers you will find in this special issue of JoLLI develop letter and spirit of Turing’s original contributions. They do not lazily fall back into the same old sofa, but follow – or question – the inspiring ideas of a great man in the search for new, more precise, conclusions. It is refreshing to know that the fertile landscape created by Alan Turing remains a source of novel ideas.

Deflationism, one of the influential philosophical doctrines of truth, holds that there is no property of truth, and that overt uses of the predicate "true" are redundant. However, the hypothetical examples used by theorists to exemplify deflationism are isolated sentences, offering little to examine what the predicate adds to meaning within context. We oppose the theory not on philosophical but on empirical grounds. We collect 7,610 occurrences of "it is true that" from 10 influential periodicals published in the United States. (...) We classify and annotate these with respect to the positions of coordinating and subordinating conjunctions that they contain. This way we investigate the contextual relationships between the proposition following "it is true that" with its surroundings. Overall, 34 different syntactical patterns are encountered. In some occurrences of "true", the predicate acts in the same manner as a performative verb does. These occurrences, having been observed in linguistically reliable media, constitute pragmatic counter-examples to deflationism. (shrink)

This is a brief reply to Herbert A. Simon's fine paper "Literary Criticism: A Cognitive Approach," Stanford Humanities Review, Special Supplement (Bridging the Gap: Where Cognitive Science Meets Literary Criticism), vol. 4, no. 1, pp. 1-26, Spring 1994.

This is the guest editor's introduction to a JETAI special issue on philosophical foundations of AI.

P.F. Strawson proposed in the early seventies a threefold distinction regarding how context bears on the meaning of "what is said" when a sentence is uttered. The proposal was somewhat tentative and, being aware of this aspect, Strawson himself raised various questions to make it more adequate. In this paper, we review Strawson's scheme, note his concerns, and add some of our own. We also defend its essence and recommend it as an insightful entry point re the interplay of intended (...) meaning and context. (shrink)

Formalizing commonsense knowledge for reasoning about time has long been a central issue in AI. It has been recognized that the existing formalisms do not provide satisfactory solutions to some fundamental problems, viz. the frame problem. Moreover, it has turned out that the inferences drawn do not always coincide with those one had intended when one wrote the axioms. These issues call for a well-defined formalism and useful computational utilities for reasoning about time and change. Yoav Shoham of Stanford University (...) introduced in his 1986 Yale doctoral thesis an appealing temporal nonmonotonic logic and identified a class of theories, causal theories, which have computationally simple model-theoretic properties. This paper is a study towards building upon Shoham's work on causal theories. We concentrate on improving computational aspects of causal theories while preserving their model-theoretic properties. (shrink)

According to the target article authors, initial experience with a circumstance primes a relation that can subsequently be applied to a different circumstance to draw an analogy. While I broadly agree with their claim about the role of relational priming in early analogical reasoning, I put forward a few concerns that may be worthy of further reflection.

In this special issue of Minds and Machines ("Situations and Artificial Intelligence") we take a close look at recent situation-theoretic research which has mostly originated within a philosophical framework but promises to have strong connotations for Artificial Intelligence workers. The seven papers which make up this special issue (three of the papers appear in Minds and Machines 9(1)) demonstrate the advantages of the situation-based approach towards problems with a definite AI flavor.

The notion of context arises in assorted areas of artificial intelligence (AI), including knowledge representation, natural language processing, intelligent information retrieval, etc. Although the term ‘context’ is frequently employed in descriptions, explanations, and analyses of computer programs in these areas, its meaning is frequently left to the reader’s understanding. -/- My aim in this paper is to offer a swift review of context in AI. I will first identify the role of context in various fields of AI. I will then (...) consider the enterprise of formalising context. The focus of my discussion will be McCarthy's (1993) proposal – a landmark study that inspired almost every logical theory of context since then – and its close variants, studied by his students. -/- (The author is grateful to Prof. Carlo Penco for his invaluable assistance with this work.). (shrink)

We extend causal theories and study actions in domains involving multiple agents. Causal theories, invented by Yoav Shoham, are based on a temporal nonmonotonic logic and have computationally tractable aspects. Since Shoham's formalism does not provide an adequate mechanism for representing simultaneous actions and specifying their consequences, we introduce the notion of counteractions while preserving the efficiency and model-theoretic properties of causal theories.

This position paper argues that in addition to the familiar approach using formal contexts, there is now a need in AI to study contexts as social constructs. As a successful example of the latter approach, I draw attention to 'interpretation' (in the sense of literary theory), viz. the reconstruction of intended meaning of a literary text that takes into account the context in which the author assumed the reader would place the text. An important contribution here comes from Harris (1988), (...) enumerating the seven crucial dimensions of context: knowledge of reality, knowledge of language, and the authorial, generic, collective, specific, and textual dimensions. Finally, two thought-provoking papers in interpretation, (Barwise 1989) and (Hobbs 1990), are analyzed as useful attempts which also come to grips with the notion of context. (shrink)

We focus on how we should define the relevance of information to a context for information processing agents, such as oracles. We build our formalization of relevance upon works in pragmatics which refer to contextual information without giving any explicit representation of context. We use a formalization of context (due to us) in Situation Theory, and demonstrate its power in this task. We also discuss some computational aspects of this formalization.

Founded in 1993, ELEKTRIK: Turkish Journal of Electrical Engineering and Computer Sciences, has gradually become better known and is fast establishing itself as a research oriented publication outlet with high academic standards. In a modest attempt to advance this trend, this special issue of ELEKTRIK brings together five papers exemplifying the state of the art in artificial intelligence (AI). Written by experts, the papers are especially aimed at readers interested in gaining a better appraisal of the applications side of the (...) AI enterprise. In all papers there is a strong emphasis on measuring the benefits of the proposed approaches in experimental contexts. The papers broadly fall into five actively researched, contemporary domains of AI: pattern recognition, genetic algorithms, fuzzy sets, intelligent design, and agents. (shrink)