Part I: Introduction. Why Language? Why Philosophy? Why Wittgenstein? - Surveying Wittgenstein's Landscape.-
Part II: Wittgenstein's Philosophy of Language and Mind. Language and Thought. Benjamin Lee Whorf. Problems With Whorf's Conjecture. Wittgenstein on Language and Thought Wittgenstein's Methodology. Wittgenstein at Work. Philosophical Investigations. 'Five Red Apples'. The 'Builder's Language'. Language Games. Language and Categorization. Universals and Particulars-An Old Debate. Wittgenstein's Approach: The Rejection of Strict Nominalism and Realism. Wittgenstein's Categories: Family Resemblances. Wittgenstein's Place in the Nominalist-Realist Debate. Forms of Life. Language Games and Forms of Life. The Big Picture: Philosophy of Language and Metaphor. Language as a Kind of Calculus. The Structure of Language is like the Dynamic. Structure of a Game. Language and Chess. Words are Like Tools and Language Use is like Tool Use. Language as a City. The Implications of the 'Language as City' Metaphor. Language as a Labyrinth. Reality and Myth: The Background of Reality on Which Language is Based is like a Mythology, and its Structure is like a Riverbed. The Foundation of Language in Instinctive Behavior. Instinctive Behavior and Forms of Life. Language and Cognition: What do We Have in Our Heads, and What is it Good for? Externalism. Psycho-physical Parallelism. The Mind and Reality: Mental Models or Scribbled Jottings? Wittgenstein and Crime: The Breakdown of the Distinction Between Inner and Outer Processes. Wittgenstein and Drama: A Dramatic Theory of Meaning. The Inner and the Outer. Imponderable Evidence (Unwägbare Evidenz). The Objective Correlative. Imponderable Evidence and Real Life. Conversational Implicatures. Wittgenstein and Behaviorism. Wittgenstein vs. Behaviorism. What is 'Behavior'? Wittgenstein vs. Behaviorism. Reductionism. Wittgenstein vs. Behaviorism. The Existence of Mental Phenomena . Wittgensteinvs. Behaviorism. Intersubjective Knowledge Wittgenstein vs. Behaviorism. Logical Behaviorism . Why Wittgenstein is not a Behaviorist. A Summary.-
Part III: Wittgenstein, Language and Information. Support for Wittgenstein's Philosophy of Mind: Robotics and 'Scaffolding.'. Where is the Mind? - The Mind: 'Who's in Charge Here?' - Scaffolding. Scaffolding and the Rational Model of Choice. Scaffolding and Computerized Information Systems. The Boundaries of the Mind. Scaffolding and the Role of Language. Mental Models. Externalism and the Philosophy of Language. Why is the 'Mind' Important for Information Systems? The Structure of Information Systems. The Fundamental Relationship in Information Systems. The Fundamental Issue of Information Systems: The 'Determinacy of Representation'. 'Escalating Uncertainty of Retrieval': The Problem with Large Systems and Indeterminately Represented Information. The Nature of Representational Indeterminacy in Information Systems. Indeterminacy in Information Systems: An Empirical Study: The STAIRS Study (examples). The 'Determinacy of Sense'- an Old Logical Problem. Description and Discrimination. The Consequences of Indeterminacy in Information Retrieval. What Do Inquirers Want? - Information Systems - A Wittgensteinean View. The 'Meaning' of a Document. The 'Diseases of Thinking' in Information Retrieval. How Do Computers Influence Information Retrieval Systems? - Managing the Retrieval of Indeterminate Information Content: Some Practical Consequences. Representing Intellectual Content. Reducing Indeterminacy in Content Retrieval. Large vs. Small Content Retrieval Systems. Using Documents Themselves as Instruments of Organization and Indeterminacy Reduction: 'Exemplary Documents' and 'Seed Searching'. Measuring the Effectiveness of Content Retrieval. The STAIRS Evaluation - A Final Look. Summary of the Design Criteria for Large Content Retrieval Systems.

"The more narrowly we examine language, the sharper becomes the con?ict - tween it and our requirement. (For the crystalline purity of logic was, of course, not a result of investigation; it was a requirement. ) The con?ict becomes intolerable; the requirement is now in danger of becoming empty. -We have got onto slippery ice where there is no friction and so in a certain sense the conditions are ideal, but also, just because of that, we are unable to walk. We want to walk; so we need 1 friction. Back to the rough ground!" -Ludwig Wittgenstein This manuscript consists of four related parts: a brief overview of Wittgenstein's p- losophy of language and its relevance to information systems; a detailed explanation of Wittgenstein's late philosophy of language and mind; an extended discussion of the re- vance of his philosophy to understanding some of the problems inherent in information systems, especially those systems which rely on retrieval based on some representation of the intellectual content of that information. And, fourthly, a series of detailed footnotes which cite the sources of the numerous quotations and provide some discussion of the related issues that the text inspires. The ?rst three of these parts can each be read by itself with some pro?t, although they are related and do form a conceptual whole.