Demonstratives like ‘this’ and ‘that’ are typically described as measuring distance from the speaker (e.g. ‘this book here’, ‘that book there’). However, they are also used in non-spatial contexts, for example to refer back to previous discourse: ‘I gave John Beloved, has he read that book (=Beloved) yet?’ or to introduce new entities: ‘now, about this book I read...’). Finally, demonstratives often develop into function words such as complementizers (‘I know that it is raining’). Earlier work suggests that the meaning of ‘this’ and ‘that’ in such cases depends on an abstract distance measured from the speaker. However, these analyses contradict each other and have been falsified with corpus data and experimental studies. This project will provide a new, unified analysis of non-spatially used demonstratives. The project builds on the novel hypothesis that ‘this’ and ‘that’ relate not only to the speaker, but to the addressee as well. It generalizes initial findings using parallel corpus research and an eye-tracking experiment. The project will thus lead to an economical, unified analysis of non-spatially used demonstratives, informing (a) the study of spatial polysemy more generally and (b) our understanding of the representation of speaker and addressee in grammar.