The subjct of this book is the first person in thought and language. The main question is what we mean when we say 'I'. Related to it are questions about what kinds of self-consciousness and self-knowledge are needed in order for us to have the capacity to talk about ourselves. The emphasis is on theories of meaning and reference for 'I', but a fair amount of space is devoted to 'I'-thoughts and the role of the concept of the self in cognition. The first part of the book constitutes a critique of different solutions to the problem of how 'I' refers, while the second part advances a positive account of 'I'. It is argued that 'I' refers indirectly through a de re sense that is based on non-conceptual content. 'I' expresses an individual concept with two components: the de re sense and a context-independent, fundamental self-concept. By interacting with the environment the subject forms belifs about herself that are essentially first-personal. To have a full-blown self-consciousness and be a competent speaker of 'I', the subject must be able to connect these indexical beliefs with general ones and thus conceive of herself as part of the objective order. The use of 'I' moreover presupposes unity of consciousness and identity over time on the part of the speake