David J. Chalmers

There’s an idea, discussed widely these days, that what we call “the universe” may be a simulation running on a gigantic computer: the Simulation Hypothesis. Now, if you like you can simply take this literally (as Hollywood has done), but for me its real interest is that it provides a fresh new way of looking at stale, often millennia-old, questions. For example, back in the 17th Century René Descartes was asking: how can I know that anything outside my own head is real? What if I’m dreaming all this, or some evil demon is deceiving me into thinking there’s a world out there when there isn’t? Were he alive today in the computer age, Descartes’ question would be more along the lines of: how can I know that I’m not in some kind of simulation?
    David Chalmers’ Reality+ explores this new angle on philosophy. It covers: the nature of knowledge (i. e. how we know about the outside world) and how far we can trust that knowledge; the nature of the world (or universe) we are looking at; the nature of the instrument (mind) doing the looking; God (as creator of that universe, and possible nature of); value (what is “good”, what is “right”)…all squinted at through the newfangled lens of the Simulation Hypothesis. In addition, there’s something even newer too—virtual reality—and, while still unwieldy at present (headset, gloves and so on), it’s certain to become ever more subtle and invasive. Much of this book is about VR and what it may already be telling us about the relationship between mind and world. Running through it is what Chalmers calls “Simulation realism”, his contention that virtual objects are real—i.e. things which are part of a virtual world are real in the fullest sense of that word; and that if something (or someone) is part of a simulation, that doesn’t make it (or them) any less real.
    Chalmers, a philosopher himself, makes his case very well, and one particular chapter out of the book’s twenty-four contained an idea so striking I’ve been mulling it over myself ever since. As for the Simulation Hypothesis itself though, I’m not, so far, persuaded by that. But it is like opening a window and letting some fresh clean air into the musty atmosphere of a philosophy class; and what’s also obvious to me is that, as we begin to design and run simulated universes ourselves, it’s going to let in a whole lot more.… (more)

A massive exploration of "technophilosophy" in which each of the 24 chapters has a question as its title. The early chapters introduce such ideas as the simulation hypothesis and the argument in its favor, the general nature of reality, and the contention that entities in virtual worlds should be regarded as real. All 557 pages are well worth reading, but the topics covered in the middle and later chapters are too numerous and varied for me to be able to comment on them concisely. One incidental point is the repeated mentioning of the imagined possibility of mind uploading: Chalmers is one of the few authors who appreciate that a process of gradual replacement (not copying) would be required for there to be any hope of preservation of personal identity. Online supplement: consc.net/reality… (more)