There are three books, actual bound paper artifacts, that sit near at hand on my desk: Webster’s New Explorer Dictionary and Thesaurus, the King James Bible and the Oxford Complete Works of Shakespeare. Though all three of these texts are available freely online, I find great value in having them within reach to flip through. Not only do they represent the foundations of modern literature but they, all three of them, are inexhaustible wellsprings of inspiration and reliable remedies to all flavours of writer’s block. For the first time in many years, there is a fourth book I am thinking of adding to this company: The Exegesis of Philip K. Dick.

The Exegesis, released earlier this month by Houghton Mifflin Harcourt, has long been a subject of speculation and whispered conversation, embodying a sort of Apocrypha of science fiction canon. It is broadly considered self-evident today that Philip K. Dick was a literary genius, a bright star whose speculative vision transcended genre. But many who have read Dick’s most acclaimed works are unaware (or wilfully ignorant) that in his later years he wrote a series of novels, beginning with Radio Free Albemuth and ending with The Transmigration of Timothy Archer, which represented a radical and surprisingly religious departure from his earlier oeuvre. Fewer still know that, during the time in which he wrote these oft-forgotten novels, Dick was furiously (perhaps compulsively) working on a grand philosophical tome which came to span some eight thousand pages. The Exegesis, edited by Pamela Jackson and Jonathan Lethem, represents the first time that any substantial part of this massive corpus has been made available to the public.

For anyone hearing of this for the first time, the question of how such a significant work by such a significant author can have gone so long unpublished must immediately arise. After all, it has been thirty years since Philip K. Dick’s death, and the man is listed in university syllabi alongside contemporary giants like Hemingway and Ondaatje. The answer, of course, is complicated. The key lies in events taking place in February and March of 1974 (or as Dick refers to it in a telling conflation of hyphen usage: 2-3-74).

Over the course of those two months, Dick had a series of visions. It’s unlikely we’ll ever know the true source of these visions — schizophrenic episode, stroke, genuine religious experience or psychotic break brought on by drug abuse — any of these is possible, some even likely. What is certain however is that they changed the author forever and came to dominate his writing and thoughts for the rest of his life. Though Dick himself intermittently ascribed them to neurological causes (“I was lithium toxic. And had a schizophrenic breakdown.”), he in time came increasingly to believe that these visions were divine, or at least paranormal, in origin. It became his life’s work thereafter to elucidate these revelations, both through his novels and through his more private writing.

Discussing Dick’s writing in the period that followed thus becomes uncomfortable. On the one hand, it is hardly controversial to say that the man was quite mad. On the other hand, even at his most unhinged, it is clear that he is far better read and far more brilliant than you or me. The Exegesis has remained so long underground in part because Dick’s children worried that its publication would harm their father’s growing reputation as a Serious Writer but also because it was, to be frank, essentially unpublishable.

Jackson and Lethem approached the task of editing Dick’s hypergraphia down to a svelte nine hundred pages with a love, humour and reverence that shines brightly through. Their ten-page introduction, a fantastic essay on Dick’s post–2-3-74 life, is well worth the cover price in its own right. For that matter, the simple act of limiting themselves to ten pages is a brave show of respect for the work. One can imagine that the desire to write a much longer preface must have been strong given that the opening line of the Exegesis proper is “In Ubik the forward moving force of time (or time-force expressed as an ergic field) has ceased.”

This is a book that you can’t make excuses for. It is a book which juxtaposes almost comically archetypal dementia like “This planet has been invaded by a benign super wise alien life form which exchanges mental contents and then uses the human some as a host” alongside such flawless gems as “To remember and to wake up are absolutely interchangeable.” It is a book wherein Dick declares that “the world has come to resemble a PKD novel” and then goes on to post-facto dissect his own earlier novels in an act of textualism-gone-mad, convinced that they were inspired by subconscious precursors of his later visions. It is a book which contains astute observations on The Tibetan Book of the Dead, on Plato’s Cave and on Heidegger, and which yet betrays a facile misunderstanding of Descartes’ Discourse on the Method. It is, on the whole, a jumbled mess. And that is not an indictment of the editors, rather the opposite. Tasked with taming a massive self-contradictory enigma, they had the discipline to resist trying to fix it.

Publishing the Exegesis is a bold move on the part of Houghton Mifflin Harcourt. The world until now has been less for the lack of this volume, but at the same time it is hard to identify the target market for such a beast. The reader who loved The Man in the High Castle and Do Androids Dream of Electric Sheep? will heft the Exegesis, flip through its dense pages, and then put it down in confusion. The enlightenment-seeker, fresh off of Gödel, Escher, Bach or The Celestine Prophecy, is unlikely to show much interest in the inchoate speculations of a science fiction author well known for his drug abuse. The Exegesis does have sufficient depth and ambition to serve as a genuine religious text, but it would be much harder to monetize than Dianetics. I am left with the feeling that, for publisher and editors alike, taking on this project must have been advised by a simple desire to enrich the world and helped along by wilful self-delusion about commercial viability. If that’s the case, God bless them.

There is, after all, one target market I can pinpoint: me. I love this book. I can open it to any page and find magic. In one of many passages of meta-commentary, Dick says: “My mind worries and scurries, contradicts itself, comes to conclusions and then arbitrarily drops them; the exegesis does not build. There is no accumulative factor.” But he is wrong. Perhaps the Exegesis retreads the same ground again and again, with precious little forward movement from beginning to end. But that is not the way to read this book. The Exegesis is a book you read as you might swim in an ocean. You submerge yourself at this point or that, absorbing it, living it. Each encounter with this text adds another layer of meaning, always building. This is a book I will be reading for the rest of my life.