Not Exactly: in Praise of Vagueness

How warm is a ‘warm day’? Where should we draw the ‘poverty line’? Are you the same person as you were yesterday? None of these questions can be given a clear-cut answer. We operate in a world full of continuous variation, relying on concepts that are not precisely defined but vague around the edges. This book, which cuts across logic, linguistics, and artificial intelligence, considers the challenges posed by vagueness, showing how vagueness is often difficult to avoid, and frequently (though not always!) useful too. It defends a perspective on vagueness that hinges on probabilities instead of crisp dichotomies or degrees of truth. Last but not least, the book shows how Natural Language Generation programs are becoming more sophisticated in their treatment of numerical information, allowing computers to use vague language judicially in their interaction with human users.