For the last five years philosopher Galen Strawson has provoked a mixture of shock and scepticism with his carefully argued case that physicalism (the view that every real, concrete phenomenon in the universe is physical) entails panpsychism (the view that the existence of every real concrete thing involves experiential being). In this book Strawson provides the fullest and most careful statement of his position to date, throwing down the gauntlet to his critics - including Peter Carruthers, Frank Jackson, David Rosenthal and J.J.C. Smart - by inviting them to respond in print. The book concludes with Strawson's response to his commentators. Galen Strawson's books include Mental Reality, The Self? and Freedom and Belief.