DAVID MCFARLAND Emeritus Fellow at Balliol College, University of Oxford, UK. He is author and editor of many books on behaviour; his most recent publications include Artificial Ethology, Oxford Dictionary of Animal Behaviour and Guilty Robots, Happy Dogs: The Question of Alien Minds. KEITH STENNING Professor of Human Communication at the University of Edinburgh, UK. His research interests include: comparison of modalities of representation, learning/teaching of formal knowledge. MARGARET MCGONIGLE Senior Lecturer in the Department of Psychology at the University of Edinburgh, UK. Her research interests include developmental cognition, executive functioning in childhood autism and Fragile X syndrome and cognitive neuroscience.