M. R. Bennett AO is Emeritus Professor of Neuroscience and University Chair at the University of Sydney, Founding Director of the Brain and Mind Research Institute, and Chair of the Mind and Neuroscience-Thompson Institute. He is the author and co-author of numerous books, including The Idea of Consciousness, History of the Synapse, History of Cognitive Neuroscience, and Stress, Trauma and Synaptic Plasticity. He is past President of the International Society for Autonomic Neuroscience and of the Australian Neuro-science Society.

P.M.S. Hacker is Emeritus Research Fellow at St John's College, Oxford, and holds an Honorary Professorship at University College, London at the Institute of Neurology. He is author and co-author of numerous books and articles on philosophy of mind and philosophy of language, and is the leading authority on the philosophy of Wittgenstein. His works include Human Nature: The Categorial Framework, The Intellectual Powers, The Passions, The Moral Powers, and the landmark seven-volume Analytic Commentary on Wittgenstein's Philosophical Investigations.