Ulrike Hahn first qualified as a lawyer, before becoming a cognitive scientist. She is a professor in the Dept. of Psychological Sciences, at Birkbeck where she directs the Centre for Cognition, Computation and Modelling. Rational argument has been a focus of her work for over a decade. She has been working on both normative accounts (concerning how we should argue) and descriptive accounts (concerning how we actually do argue), particularly with respect to so-called fallacies of argumentation. For her work on human rationality, she has received the British Psychological Associations Cognitive Section Prize, the Swedish Research Council’s Hesselgren Professorship, and the Humboldt Foundation’s Anneliese Maier Research Award. She is fellow of the Association for Psychological Science and the German National Academy of Science. She remains cautiously optimistic about human rationality and the capacity for rational argument to prevail.