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for the belated reply, . . . ’, ‘Congratulations!’), and so on. But in these cases, too, our utterances carry information, and that they do so is essential: a question must convey what information is requested; a directive must specify information about what is to be done, or to be refrained from; a warning or threat must identify a particular situation or event; and if we don’t convey what it is that we regret, or what we are happy about, the point of our speech is lost. These humdrum observations also illustrate a further point. Not only do natural language utterances involve information about a variety of types of situations: factual and possible, past, present and future; they also convey information about the specific attitudes that natural language users have concerning these situations: that the speaker takes them to be factual, or merely possible; that they are to be avoided, or to be realised, by the hearer; that the speaker regards them with regret, or with joy. Thus the information carrying capacity of a natural language encompasses not just what its expressions are about, but also the various attitudes that its users may have towards that. Another way in which information might be conveyed is more indirect than in the examples above, where it is coded in the syntactic form or indicated by a particular expression or turn of phrase. Making use of the context in which an utterance is produced, for example by relying on the presence of certain expectations on the part of the hearer, we may also indirectly convey information about a certain situation. For example, when answering a question about the whereabouts of Jane by means of a disjunction (‘She’s either in Paris, or in London, with Mary’), we indicate that we do not know exactly where she is. This is information that isted. However, an addressee who expects the speaker to be as co-operative as he can will pick up this information without hesitation. And it doesn’t stop there. Besides utterances of the above kinds there are those which serve various social purposes: greeting someone, acknowledging a gesture or utterance she is making, expressing concern or empathy. Many utterances we use to such ends — ‘Hi, how are you?’, ‘I am sorry to hear that’, and so on — are formulaic. They carry information, not in virtue of being about something and expressing an attitude to that, but by being fixed through special conventions, which bypass the general mechanisms by which information is associated with linguistic form. But these utterances do carry information nonetheless, as is indicated by the fact that the purposes they serve can as a rule also be accomplished by means of other, non-formulaic utterances. Yet another way in which information is conveyed by natural language is through mechanisms that relate a specific utterance to its linguistic context. After all, an utterance hardly ever occurs on its own, out of the blue; usually it is part of a larger whole, a text or a conversation, that serves a specific purpose and accordingly may have a specific form. When it is part of such a larger textual or conversational complex an individual utterance may contribute to the meaning of that complex as a whole through mechanisms that relate it to other parts of the complex. The use of pronouns to refer to an entity mentioned previously in a conversation (A: ‘I met John the other day.’ B : ‘How’s he doing?’) is a simple example; the specific form of a question – answer dialogue, in which answers more often than not are fragments of complete sentences, yet do express complete propositions (A: ‘Who’s chairing the meeting?’ B : ‘Bill.’), provides
Information in Natural Language
Hans Kamp∗ Martin Stokhof† To appear in: Pieter Adriaans and Johan van Benthem (eds), Handbook of the Philosophy of Information, Elsevier, Amsterdam

Introduction
Natural languages are vehicles of information, arguably the most important, certainly the most ubiquitous that humans possess. Our everyday interactions with the world, with each other and with ourselves depend on them. And even where in the specialised contexts of science we use dedicated formalisms to convey information, their use is embedded in natural language. This omnipresence of natural language is due in large part to its flexibility, which is almost always a virtue, sometimes a vice. Natural languages are able to carry information in a wide variety of ways, about a seemingly unlimited range of topics, which makes them both efficient and versatile, and hence useful in almost every circumstance. But sometimes, when pinpoint precision is what counts, this versatility can get in the way, and we make use of formal languages, such as those of mathematics. The variety of ways in which the use of natural language involves information, reveals itself immediately if we look at the various functions that utterances of natural language expressions may have. First, many of the utterances we produce serve to directly impart information to our readers or listeners — usually information which we take to be new and of interest to them. We describe situations, stating what we take to be facts (‘Mary is in Paris’), or contemplating what we regard as possibilities (‘John might be accompanying her’). This declarative use of language is perhaps the most obvious way in which natural languages are used to convey information. But, of course, this doesn’t hold for all utterances. We also ask questions (‘What time does the meeting start?’), in order to elicit information rather than to impart it; we give directives (‘Open a window’, ‘Stay away from her’), in order to get the other to do certain things, or to keep him from doing them; we issue warnings and threats (‘Look out, a bus!’, ‘If you do that, I’ll tell the boss’), we express regret and joy (‘I apologise
Institut für maschinelle Sprachverarbeitung, Universität Stuttgart ILLC / Department of Philosophy, Universiteit van Amsterdam . We would like to thanks the editors for their patient support and Menno Lievers for his detailed critical comments, which have led to many improvements. Obviously, only the authors are to be held responsible for the end result.