Raymond Tallis is Professor of Geriatric Medicine in the University of Manchester and a consultant at Hope Hospital, Salford. He is the author of The Clinical Neurology of Old Age and Epilepsy in the Elderly. As well as his medical works he has published short stories, verse and philosophical and critical essays (including a critique of Lacan in PN Review 60). In two books published last year, Not Saussure (Macmillan) and In Defence of Realism (Edward Arnold), he attacks the philosophical premisses of the 'New Criticism', and argues for the progressive potential of realist fiction. He here restates the case for the defence in conversation with David Watson.

David Watson:One basis of your argument in In Defence of Realism, is the notion of 'fact'. You argue that language is founded on a referential reality which offers an empirical guarantee of factual truth, and that factual statements can be clearly distinguished from mere evaluations. From this you derive the notion of fictional 'plausibility' - a benchmark of a novel's fidelity to life, and also of its value. Is this a fair summary?

Raymond Tallis: Let me deal with fact first and then with fiction.

Since Nietzsche declared that 'there are no such things as facts, only interpretations', every Sixth Former knows that facts are relative - to the subject's perceptual mechanisms, to the language in which they are expressed or to the interests of the group on behalf of whom they are being expressed ...