Jacques Roubaud, the legendary poet, mathematician and member of Oulipo (l'Ouvroir de littérature potentielle or 'Workshop of Potential Literature', an international group of writers and mathematicians), is 86 years old, but his ideas on poetry seem to be more innovative than ever. Melanie Godin (director of Les Midis de la Poésie) and Renaud Lambiotte (professor in mathematics in Oxford) talk to him about the dividing line between lyrical emotion and mathematics.