Arguing that one way of understanding cyberspace is as an attempt to realize an electronic version of heaven, this book begins with the medieval definition of the world as spiritual space. The author traces the emergence of modern physics with its emphasis on physical space, and then presents her thesis: that cyberspace, an outgrowth of modern science, nevertheless represents a return to medieval, spiritual concerns. Cyberspace posits the existence of a genuine yet immaterial world in which people are invited to commune in a non-bodily fashion, just as medieval theology brought intangible souls together in heaven. How did we get from seeing ourselves in soul-space (the world of Dante and the late-medievals) to seeing ourselves purely in body-space (the world of Newton and Einstein)? Margaret Wertheim offers a description of this transition and the new shift propelled by the Internet.