Book excerpt: A leading philosopher takes a mind-bending journey through virtual worlds, illuminating the nature of reality and our place within it. Virtual reality is genuine reality; that’s the central thesis of Reality+. In a highly original work of “technophilosophy,” David J. Chalmers gives a compelling analysis of our technological future. He argues that virtual worlds are not second-class worlds, and that we can live a meaningful life in virtual reality. We may even be in a virtual world already. Along the way, Chalmers conducts a grand tour of big ideas in philosophy and science. He uses virtual reality technology to offer a new perspective on long-established philosophical questions. How do we know that there’s an external world? Is there a god? What is the nature of reality? What’s the relation between mind and body? How can we lead a good life? All of these questions are illuminated or transformed by Chalmers’ mind-bending analysis. Studded with illustrations that bring philosophical issues to life, Reality+ is a major statement that will shape discussion of philosophy, science, and technology for years to come.