ABSTRACT

of the speakers, so that Fred will know something that Sally does not know, or Sally something that Fred does not know. In addition, there will be partly known information: Fred or Sally, or both, may partly know something or know parts of something, but not necessarily the same parts. And Fred or Sally, or both again, may believe that the other knows something that the other actually does not know. As we can see, there are numerous possible permutations in who knows what, who believes who knows what, and so on. Again, there are predictable consequences: conversation can proceed only on the basis that the participants share a set of beliefs, that is, certain things must be known to all parties; others may be known; some will have to be explained; questions may be asked for clarification; difficulties will be negotiated or cleared up somehow; people will be understanding and tolerant; and the various processes that are involved will be conducted decently. If only one participant in a conversation refuses to subscribe to these beliefs and to conduct himself or herself accordingly, the others will become irritated, confused, or frustrated, and may well abandon any attempt to continue what they have begun.