Marina Warner is one of our most erudite and morally serious writers, a historian of how forms and figures become the repositories of larger cultural values and meanings. In her earlier books she explored, among other things, how the Virgin Mary became “so satisfying a symbol”; how the female form became an allegory for desires and virtues that real women were thought to lack–justice, liberty, wisdom; and how the short career of Joan of Arc came to lodge “in the minds of people who heard her story” through the ages. Warner is interested in the ways that the really big furniture of our minds–religious as well as secular worldviews–came to be there.

Phantasmagoria is her most ambitious book, an intellectually dazzling struggle with how the modern world (beginning roughly in the Renaissance) has imagined the stuff of souls, the nature of the psyche, the “mysterious, elusive, and ethereal” thing that somehow distinguishes the truly dead from the living and makes us what we are. It is also her most challenging book, a wonderfully suggestive though not rigorously analytical work that often reaches further than it can grasp and admits as much. After all, the “enthralling borderland between animation and lifelessness” is not a well-lit terrain, however irresistibly it draws our attention.

In one sense the word “phantasmagoria” captures precisely what the book is about: how various technologies–wax figures at Madame Tussaud’s, photographs, movies, digital images–became vehicles for imagining something that animates and gives life to what is lifeless. It is a late-eighteenth-century neologism that refers to both the optical illusion of a “phantom”–an apparition or spirit, an appearance that deceives–and the instrument first used in 1798 by Belgian inventor Étienne-Gaspard Robertson to generate these creatures. (In fact, Warner shows, the seventeenth-century polymath Jesuit Athanasius Kircher had already begun painting images of spirits on glass slides, one of several technologies for “producing and rendering the operations of fantasy.”) But if the means by which we represent what we know to be unreal were all that interested Warner, her book would not be so compelling and so rich.

Phantasmagoria is instead a history of the “logic of the imaginary,” which encompasses, among others, convinced spiritualists who believe in a still enchanted world; experimental thinkers like William James who felt that spiritualists might be onto something; modern-day religious fundamentalists who read the Book of Revelation as the literal truth; and critics of enchantment who nevertheless recognize that we do imagine life in inanimate things, from Karl Marx, with his theory of commodity fetishism, to Walter Benjamin, with his concept of the “aura” surrounding a work of art, to artists who have digitally constructed the life of Japanese cartoon figures. Warner does not distinguish between these levels of reality, nor is she bound by chronology. This elasticity of method allows her to traverse centuries and circle easily through the chaotic contemporary “mental skyscape” of spirit–an explosion of multimedia images–and the “wild heterogeneity of the Hellenistic world” thousands of years ago.

Warner’s story of spirit begins solidly, however, with three corpses: the mummified body of Santa Caterina de’Vigri in Bologna’s Church of Corpus Domini; the remains, in a grave only yards away, of the eighteenth-century scientist Luigi Galvani, who studied how electrical currents seemed to revivify dead frogs (this suggested to Mary Shelley the way Dr. Frankenstein could give life to his monster); and the famous “auto-icon” (the mummified body) of philosopher Jeremy Bentham, which sits in University College London and occasionally presides over Senate meetings there. The dead saint remains somehow present in an uncorrupted–or at least recognizable–body that testifies to the purity of the soul that once inhabited it and still gives it miraculous properties (not least of which is resurrection). The dead scientist is presumably dust, although we are reminded that life was but a spark. The dead materialist philosopher is strangely all there, evoking an eternal present, because what we see is the seat of personhood, at least as he understood it. How we think about what these bodies mean depends on how we answer the question of what animates matter.

Warner offers three ways to get at this. The first, most consistently pursued and lavishly documented, is a history of the forms, materials and technologies–from the wax of death masks and anatomical models to air and clouds, the imagined ether of space, mirrors and the magical projections of film and binary bits of the Internet–through which spirits have made themselves visible to the senses. This history does not follow a chronological order except insofar as still pictures came before moving ones. (Contemporary artists are discussed in chapters about sixteenth-century clouds or the seventeenth-century camera obscura.) There is more than a hint in this tale that each of these phantasmagoria has an intrinsic life of its own, as if it were waiting to become a vehicle of spirit in almost any time or place. (This history of enchantment is more than a little enchanted itself.) But the crucial point about phantasmagoria is not their illusory quality but their status as artifacts, as things made. “Art” creates spirit and psyche out of matter.

In successive chapters, Warner expands on how particular materials and techniques–the substrata, so to speak, of the imagination–bring the unseen and unseeable to light, each in its own particular way. Wax, for example, has the capacity to take on the colors and even textures of skin. It emphasizes the peculiarity of life through its capacity to represent deathlessness; it fixes the corruptible body in preternaturally real anatomical models of corpses that seem asleep. It is as if the modern techniques of wax sculpture could somehow represent a vivifying principle in a way that older religious forms could not, as if it could make the unseen palpable in ways that the Eucharistic wine and wafer could not. (Wax tablets, one might add, were a substratum of memory for Plato.)

There is a chapter on shadows–in chiaroscuro but more pointedly in cut-out silhouettes and later in black-and-white photographs. Because the light that created these images touched the thing itself, they somehow transmit something of the essence of the living original. Another chapter is on clouds: God dwells in them; angels lounge, dance and sing on the great billowing whiteness of Baroque paintings. Clouds also make themselves into shapes that diviners interpret and ordinary people dream in. And then there are chapters on photography and moving pictures of various sorts that create new possibilities: Marilyn Monroe, dead but ever young, can be conjured up with the click of a laptop; the uncanny is an everyday staple of contemporary media; all manner of illusionism is possible as never before.

Embedded in this survey of how spirit has been imagined is an intellectual history of subjectivity. This history is sketchier and far more speculative, but it usefully suggests the ways technology might determine how we understand personhood itself. The trajectory is roughly from the Newtonian sense of the mind as a kind of objective instrument to the “Romantic, Kantian, subjective percipient”–spirit goes inward–to the post-Victorian period, in which cameras and other instruments produce an ever stranger and unsettling form of “individual quiddity.” Warner’s dystopic image for this stage comes from Edgar Allan Poe’s story “The Domain of Arnheim,” in which spirits Poe calls “earth angels” “assemble and reassemble meaning in the world as they see fit.” New technologies used to define us in various ways–ID cards with digitalized data; EEG, CAT, PET and scans of various sorts; new sorts of infotainment; indeed, a whole panoply of contemporary media–have, in Warner’s view, weakened our power to imagine and left us feeling as if we and our world were being imagined by uncanny creatures who had passed “beyond death.” The point seems to be that we have lost control of our souls.

Near the end of the book a third history comes into focus, a morality tale that gathers force in Warner’s fierce final chapters: one on the Book of Revelation, with its hallucinatory violence at the End of Time; the other on zombies, those numb, vacant creatures emptied of selfhood and devoid of will who “embod[y] the principal ghostly condition of our time, the successor of waxworks, shades, ghosts, apparitions, and the host of paranormal spirits who have figured the dead in public since the eighteenth century.” The Book of Revelation suffuses the language of our leaders: Bush’s fondness for calling his term of office his “watch” echoes the call to “be watchful” (Revelation 3:2); the catchphrases “axis of evil” and “war on terror,” Warner suggests, are self-conscious archaisms redolent of the Apocalypse. Zombies, which first arose in early-nineteenth-century Caribbean slave culture as phantasmic doppelgängers of men and women who had been robbed of personhood and freedom, re-emerge in the late twentieth century as the phantasmic expression of a new kind of dispossession: that of late capitalism.

The not-so-hidden subtext for Warner’s morality coda is Iraq and more generally the politics of the world after 9/11: the religiously inflected rhetoric of Bush and Blair, who seem to regard the “war on terror” as if the Whore of Babylon were the enemy; media that make real pain and horrendous acts disappear in images; and TV news in which real events are scarcely distinguishable from stock images. Digitization, above all, has turned “reality into dream, dream into act, and myths into reality.” In short, Warner suggests, the imagining of the spirit world has taken a terrible turn; what was once “real” and wholesome has turned corrupt and corrupting. Although the arc of her argument is never quite spelled out, her point seems to be that earlier phantasmagoria were representations of a reality beyond the visible–of the soul, the vivifying principle, the spirit of humanity. They helped us think through what–to return to the beginning of Warner’s book–the bodies of the saint, the scientist and the philosopher mean. Today, on the other hand, phantasmagoria hide meaning and deny reality; spectacle supplants, even obliterates reality by creating a counterfeit world through the black magic of technology. Not just single events but whole wars–the first Iraq war, for example–can simply disappear.

Artists, writers and performers, Warner insists, need to resist this hollowing out and perversion of the imagination through new ways of imagining what she calls ensouling: “New metaphorical constellations need to be discovered in the skies that language and imagination unfurl before our eyes.” In an age of dehumanizing technologies, those who care about human subjectivity need to “dream differently.” She offers scores of examples of how art and, more generally, technology might help us to do this in a disenchanted–or more dangerously and malignantly enchanted–age. Some are poignantly ridiculous: Cotton wool was invented, we learn, by a Victorian doctor from Birmingham named Joseph Sampson Gamgee just in time to become, along with cheesecloth, the “most used [and highly photogenic] correlate of spirit substance” of the late nineteenth century. It is what ghosts–and angels in school pageants–wore. Other examples appear in suggestive asides. Those who attributed to “savage peoples” the belief in photography’s capacity to steal the soul, she suggests, may have been projecting their own shame in having the very same “unscientific” intuition–and desire–that the new technology could transfer personhood through light to paper.

Warner draws other examples from modern art. There is a wonderful story about Arshile Gorky angrily getting out of a car in the middle of the desert because his traveling companion, Isamu Noguchi, refused to recognize that clouds were forming Uccello’s Battle of San Romano in the sky. (Seeing things in nature goes way back: Piero di Cosimo saw things in the spit of hospital patients, and Leonardo imagined rocks and streams in the stains on walls.) And in sculptor Ron Mueck’s plastic and resin hyperreal bodies, Warner finds figures that eerily “shiver on the very verge of life.” Her point is not simply that Mueck is skilled at producing the effect of the real; his figures are too big and too disarticulated for it to be just a matter of realism (baby heads do not exist isolated from bodies). For Warner, Mueck’s sculptures, like wax figures, suggest that even in our supposedly disenchanted world there is an animating principle, a spirit that gives life to matter.

In a book so richly imaginative there is also a lot to argue with. There is, first of all, Warner’s moral pessimism, her conviction that technology generally determines experience and that contemporary media overdetermine it in dehumanizing ways. It may now be hard to retrieve personal memory from a surfeit of representations of ourselves; digital images may stand in for direct experience; popular video-game images of apocalypse may well elide the reality of pain and suffering of the carnage they represent. Yes, one might say, of course. Seeing ourselves and our memories through new technologies must make a difference. But as early-twentieth-century sociologist Maurice Halbwachs pointed out, memories are always social and refracted through those of others; they are never–or never just–our own. Human, and perhaps also animal, suffering and pain are never culturally pure; their reality takes shape through the meanings we give to them, and it is by no means clear that they are any less real now than they ever were. If clouds are no longer sufficient to convey “the unpolluted, uncontaminated zone of the spirit,” as Warner writes, this is not because in the old days the skies were clear. The billowing clouds of Constable were painted at a time when the air of London and other great European cities was fouler than it had ever been before. Urban air pollution, in the West at least, was probably worse in the seventeenth and eighteenth centuries than it is now.

More important is the question of just what Warner thinks about the existence of phantasmagoria. I understand that if we take the term literally, this is a nonissue. They are all creatures of the imagination, of art and technology. But not all phantasms are the same. Whether or not clouds have meaning is not something that can be established empirically. Those who believe they do may be deluded or mistaken, but they are not gullible and cannot be disabused of the idea through experiment. But the belief that photographs scientifically record spirits or fairies or ectoplasm–the new stuff of souls–coming out of various orifices is another story. Warner says that her most unexpected finding is that Victorian science applied “rigorous laboratory methods to the proving of ghosts and a spirit force.” Indeed, some prominent scientists–members of the Society for Psychical Research, for example, like Sir Oliver Lodge, one of the pioneers of electromagnetism research; Sir William Crookes, who discovered thallium; and Charles Richet, the 1913 Nobel laureate in physiology–believed they were doing just that. But many others showed again and again that their colleagues had been victims of fraud; as early as the late nineteenth century ordinary photography manuals showed how to produce “ghosts” via double exposures; prominent mediums were repeatedly unmasked. While radio waves and the cathode ray tube and telegraphy and photography did allow new ways to imagine spirits, as Warner argues, they also provided ways to show that spirits do not exist.

The ontological status, not of spirits but of voices, also haunts Daniel Smith’s Muses, Madmen, and Prophets. For Warner voices are what they were for Aristotle: “sound produced by a creature possessing a soul.” They are pneumatic, borne by air, imagined as “out there.” The voices that Smith writes about are in the head, and his project is to figure out what they are doing there, what they mean today and what they meant in ages past. His overarching claim is clear and cogent. Voices once had a complex relationship to the divine and to the soul; in our age they have been reduced to symptoms of psychic pathology. He makes this claim through three distinct approaches. The first is intellectual: hearing voices as pathology, as a correlate of obsessive-compulsive disorder or as a symptom of schizophrenia or some other illness; as the communication of the gods. The second is emotional: most movingly, Smith’s effort, through empathy, through participating in various simulations and through reading first-person accounts, to understand the voices that had spoken to his father all his life without the son knowing. And finally moral: an effort to understand how different societies have interpreted hearing voices.

Here he offers three case studies: that of Socrates, where the question, as Smith sees it, is the relationship between reason and the daimonions who spoke to him; that of Joan of Arc, whose voices, whether real or not, gave her joy and without which she was bereft; and that of the clearly mad Daniel Paul Schreber, who wrote brilliantly about his inner voices, insisting, like St. Joan–but in the language of a nineteenth-century German lawyer–that they gave him a “great and unshakable” knowledge of God and the universe. Schreber’s is the voice of resistance to psychiatry, a leitmotif of the book.

Smith has construed his topic very broadly. This has the advantage of any really good survey. It has the disadvantage of making for something of a sprawl, a shaggy portmanteau that bulges with incommensurable phenomena. The literal hearing of voices–a simulation exercise in which he hears through earphones “it’s you; you are the one”–jostles with the whole range of metaphoric voice-hearing like the voice of conscience or of an inner self (Rousseau’s view) or of God within but not outside (St. Augustine’s view). The inner voices of the indubitably insane shade over into the troubling voices of his father and the ordinary voices we all hear in conversations with ourselves. So broad a sweep means that serious philosophical discussions by leading scholars of ancient philosophy about how we might understand Socrates’ interpretation of his “divine signs”–in the Apology they are simply voices (phon&macre; tis)–are brusquely and unpersuasively dismissed, as are the linguistic problems involved in such questions.

In the ancient Greek world it was commonplace to think of voices as signs rather than as auditory hallucinations in the sense of what Schreber might have heard. As Alexander Nehamas, a scholar of ancient philosophy at Princeton, has noted, Plutarch thought that Socrates’ daimonion was a sneeze, whether “his own or that of others.” So “if another sneezed on his right, whether in front or behind him, he would perform the action (he was considering), but if it was on his left, he would desist.” Voices in this sense are omens, like birds and clouds, which is only to say that auditory hallucinations perhaps cover so broad a range that the term risks losing meaning.

Smith, like Warner, is careful to reserve judgment on the question of ontology. It is not our duty, he says, to adjudicate the question of whether or not voices have meaning or even whether they really exist. They are real by virtue of their presence for those who hear them, and we have an obligation to listen to their claims “when they arrive, wherever they have come from.”

I do not want to argue against tolerance. Certainly the contemporary study of religion and more generally of the world of spirits demands a certain suspension of judgment. But the question remains for the citizen if not the scholar in each of us: Is the world enchanted or is it not? Is there a divine or supranatural order that we can get at by interpreting the clouds or blots or religious texts, or is there not? I am not sure one can wax eloquent about the rich capacity to imagine spirits in one age and then feel repelled, as Warner does, by the apocalyptic rhetoric of an American President who regards God as a foreign policy adviser and the Apocalypse as a source for his speechwriters.

BBC News reported in 2004 that a 10-year-old toasted cheese sandwich that purportedly bore the image of the Virgin Mary had sold on eBay for $28,000. The Internet casino owner who bought it said that it was a wonderful bit of pop culture, would help raise money for charity and would generally raise people’s spirits. On the other hand, Mrs. Duyser, who sold the sandwich, remarked that it had not gone moldy in the ten years since it had been made: a lunchbox Santa Caterina of sorts. Of course, one might not have to choose between these interpretations. Perhaps it was no more than a Mary rabbit’s foot to Mrs. Duyser, who attributed a $70,000 gambling win to the luck-bearing toast Madonna. But even as we laugh at this story as camp, it is also scary, as a trawl of web-based Virgin Mary sightings quickly makes clear.

I can understand the power of phantasmagoria and of the need to imagine what is human about us in terms other than matter and motion. In her book on the Virgin, Warner reports that after she had lost her faith, she stood with tears in her eyes in the nave of Notre Dame, “furious at that old love’s enduring power to move me.” Neither she nor Smith is ready to give up on enchantment, but it may be time to abandon it in the public domain. Either we are alone in the universe and must make the best of it or we are not. In these days, when people whose bumper stickers read “If the driver of this car disappears it is the Rapture” have the ear of our President, I am not sure we can afford to remain agnostic.