Sebastian Smee’s compelling book, The Art of Rivalry, explores four volatile friendships – between Matisse and Picasso, Manet and Degas, Bacon and Freud, and de Kooning and Pollock. Smee, art critic for The Boston Globe, chronicles the intense relationships of these eight famous artists, charting the breaking points that led each to an artistic breakthrough for each one. Ashleigh Wilson, arts editor for The Australian, talks to him about the nature of influence.