Anil Seth’s quest to understand the biological basis of conscious experience is one of the most exciting contributions to twenty-first-century science. What does it mean to “be you”—that is, to have a specific, conscious experience of the world around you and yourself within it? There may be no more elusive or fascinating question. Historically, humanity has considered the nature of consciousness to be a primarily spiritual or philosophical inquiry, but scientific research is now mapping out compelling biological theories and explanations for consciousness and selfhood.