“Dick never intended The Exegesis for publication, and aside from In Pursuit of VALIS, a tiny selection of extracts from the book that was brought out in 1991, it has remained a thing of legend only. Until last month, however, when Houghton Mifflin Harcourt brought out a huge 900-page volume, co-edited by Jonathan Lethem and Pamela Jackson. It’s still only about one tenth of the whole thing, but it’s a start. But what, if anything, does this text have to offer people who are not Philip K Dick?”