The Unknowable in Early Modern Thought: Natural Philosophy and the Poetics of the Ineffable. KevinKilleen. Stanford, CA: Stanford <scp>UP</scp>, 2023. x + 262 pp. <scp>ISBN</scp> 13: 9781503635395. $90.00 (cloth).

This book should come with a warning: read with care, as severe fits of dizziness and general existential disorientation may ensue. Dizziness, or vertigo (to use a recurring term in this book), indeed lies at the heart of Killeen's remarkably energetic foray into the intractable realms of the unknowable in early modern thought and its attending poetics of the ineffable. As anyone who has ever written, or has tried to write, about the ineffable (in all of its possible forms or manifestations) will know, there is something frustratingly pyrrhic, Kafkaesque even, about filling reams of paper with words purporting to say something about which nothing can ever be truly said. However, the central irony about ancient apophatic traditions of negative theology in Western thought is that they excel at generating speech. The denser the black hole at the center of things (and black holes famously have infinite density), the more desperate the attempt of lighted language to escape its gravitational pull. For some, this is a road to a kind of madness; for others, it is a road of relentless scholarly and linguistic inquiry in search of the limits of knowledge and discourse itself. Killeen's intervention in these traditions, both as a scholar who documents and observes, but also as a keen interloper peering into forbidden mysteries, always reaching for an appropriate turn of phrase, is both timely and effective, its grand sweep at once mesmerizing as at times baffling. In broadest terms, Killeen's project is to shed light on myriad apophatic discourses in early modern thought, or what he terms a “very particular array of unthinkables” (3), that reanimate and repurpose for modernity the ancient theological poetics of ineffability that have stood at the heart of Western mystical traditions from antiquity. Killeen invites his readers to stand on a viewing deck from which a staggering panorama of early modern apophatic discourse unfolds, with numerous surprising and illuminating turns. This is a landscape that encompasses many different writers and thinkers, some of whom would rarely be grouped together and most likely would have baulked at the thought of their intellectual neighbors in this volume—from the German mystic Jacob Boehme and the radical political-prophetic ramblings of Anna Trapnel, to the warm humanistic musings of Thomas Browne, the scientific imaginary of Margaret Cavendish and Robert Boyle, and the august poetry of John Milton (not in this order). Killeen stretches the terms of ineffability to encompass a variety of topics and concerns in seventeenth-century natural philosophy and scientific thought to make the case that the thoroughly theological and mystical concepts of apophatic discourse migrated into new and surprising discourses, undergoing a “disciplinary shift” (5). Killeen's apophatic, therefore, can be found in the very fabric of creation and cosmology, in the shifting, vertiginous perspectives of immanent eternity, as well as in the minuscule and infinitesimal, in Lucretian atomic poetics, in metaphors of disorientation and voracious restlessness, and, more traditionally, in radical prophetic enthusiasm as well. What binds these varied and equally restless inquiries is careful attention to style and rhetoric, showing remarkable alertness to the manner by which select early modern thinkers with a scientific bent, steeped to varying degrees in mystical discourse and prophetic aspirations, were all in a profound Greek sense poets, or makers, crafting realities with and through language. Indeed, it is curious how often in this book Killeen comes close to suggesting that the authors he is surveying were not merely exploring the edge of their reality but were actively engaged in various forms of poetic solipsism. Just as the unknowable, as Killeen rightly cautions, should not be confused with simple epistemic bafflement, so it appears that the style of the apophatic Killeen detects in Browne, for example, “ravenous . . . prone to inattention and never able to rest” (17), is often enough a self-generating system of hyper-reality that can only be made sense of once grounded in modes of experience or doctrine we might recognize as stable or provisionally “real.” The strength of Killeen's argument is precisely that he allows the reader to remain grounded in solid scholarship and the comforting outlines of facts even as the vistas of the various chapters whirl the imagination into impossible conceptual and poetic mindscapes. At a glance, the book's structure puzzles. While the chapters are suspended within an approximate chronology of sorts, the argumentative structure is largely associative and intuitive. As Killeen presents it, the book's “center of gravity is seventeenth-century England” while also conceding, rightly, that “European thought was, of course, distinctly porous” (4). This porousness allows Killeen to move deftly between extremely varied genres, rippling with resonances and echoes, which solidify into something more concrete as the book progresses. The book opens on solid scriptural ground that then soon begins to shift with an important reassessment of the reception of the Book of Job in early modern thought as setting a precedent for “an apophatic poetics of creation” (9), later on analyzed more precisely as the poetics of a “monumental geo-architecture” (32). This chapter offers an important addition to the more traditional readings of Job in Protestant early modern culture as the paradigmatic text of patient suffering, showing how its counter-narrative of creation, spinning out of the whirlwind, offered a language for a new kind of apophatic natural theology. The second chapter turns to the much-neglected mystical ravings of Jacob Boehme in his Mysterium Magnum and what Killeen discusses as his “natural philosophy of the eternal” (11), which assumes to expose the bare mechanics of an invisible cosmos whose grammar of creation, like some sort of primary code, can be glimpsed and decoded whether reading the Scriptures or observing clods of earth. In trying to make sense of Boehme, Killeen speaks of a “theopoetics” explained as “a writing around and athwart the unreckonable and the unknowable” (65). As so often in this book, Killeen's analysis here deliberately frustrates logic even as an interpretive pattern emerges, perhaps better described as a distinct rhetorical and poetic texture that nevertheless then “thickens” into “reality” (74). This same approach is then extended into a similar discussion of Thomas Browne's eccentric The Garden of Cyrus, which helps Killeen clinch his argument that these discourses migrated across genres and habits of thought, from the strictly theological to the more broadly scientific and humanistic. The next two chapters proceed by a similar method where the scientific and theological are shown to bleed into one another in the brewing of all manner of strange textual concoctions. With the scientific bent of Browne's mind still holding our attention, Killeen next turns to Boyle and Cavendish and “early modern encounters with the miniscule” (13), this time producing a new variant of apophasis labeled a “poetics of distortion” (13). This chapter is especially intriguing for showing the many surprising ways in which traditional apophatic discourse all too often dismissed as “mystical” engages and meets in the period with the ghost of Lucretius and his atomic theory. The resulting foray into the Restoration science of microscopy—in itself fascinating—ends up placing Cavendish especially in a new and interesting light as a writer whose vitalist scientific musings about “knowing matter” were deeply rooted in apophatic poetics. In some ways, this is the book's most accomplished and important chapter that qualifies in crucially important ways the still widely held belief that the scientific revolution of the late seventeenth century discarded the “metaphorical capacity of reality” (120). As Killeen shows, systems of logic that buckle under the strain of the unknowable do not then always retreat in the period onto safe ground, but precisely turn to the language of the unknowable to extend even further the limits of human curiosity. Consequently, the lurching move in the next chapter to a discussion of Anna Trapnel's bizarre prophetic rantings indeed causes vertigo, but here, too, the mists soon clear to reveal a strong and confident strain of argument that not only engages learnedly with the wider political and theological implications of prophecy in England's revolutionary years, but allows other parts of the book to appear in a new light. Perhaps this sudden turn into a more traditional discussion of radical prophetic enthusiasm might seem to some as mere tokenism, but it sits well with the book's wider aims when, again, we are reminded that Killeen's deepest interest is in language itself and its manifold ways of “waking up,” to borrow his phrase from the Trapnel discussion. All this brings us in Chapter 6 to Milton and a reassessment of his apophatic poetic engagements in Paradise Lost. In many ways, this chapter functions as a lengthy epilogue to the whole (which the actual Epilogue only summarizes), largely because it reverberates with the metaphors and insights that have accrued from the reading in the chapters that came before. As a stand-alone piece, the chapter on Paradise Lost is rather humble in its aspirations. Tipping his hat to a vast array of Milton scholars (some of whom would be shocked to discover themselves named in the same sentence), Killeen turns primarily to Milton's cosmology and the ineffable texture of the poem's untenable spaces of hell, Chaos and the created world, and the ever-shifting perspectives among them. Grouping his insights into the poem's texture under the rubric of a “theology of disorientation,” Killeen makes a case (perhaps surprisingly not dissimilar to that of Peter Herman's Destabilizing Milton) for seeing in the poem's manifold contradictions its essential theology (168). That is, as Killeen later puts it, “the poem's incongruities, its dissonances and contradictions, are structural, load-bearing facets of Milton's theology: we cannot reason our way beyond them” (173). Miltonists, much like their object of study, are a quarrelsome lot and not all will agree with Killeen's metaphysical fence-sitting that insists that what confuses us in the poem is not only deliberate but constitutes its essential theological structure. But this would be uncharitable. Killeen's Blakean Milton is one for whom, much like Boehme (for whom Killeen rightly says Milton would have had no patience), the eternal is always immanent in created matter, glimpsed in the poetic imagination as a “kind of pulsating reality, something that sits outside the real, the created world” (180). Killeen is especially strong here on what he analyzes as Milton's “Doppelgänger Hermeneutics,” especially in hell, where the famous similarities in the poem's post- and prelapsarian realities collapse to generate in the reader a deliberate theological as well as ethical disorientation. Such claims about Milton's epic poetry, in and of themselves, are not entirely new, but they do rise to something of unique import when viewed against the backdrop of the book's preceding chapters. The link with Boehme, Browne, Cavendish, and even Trapnel, not to say the embryonic echoes of Job's whirlwind, come together to show convincingly how firmly rooted Milton was in the apophatic discourses of his age, even if he liked to imagine his effort was “unattempted yet in prose or rhyme” (Paradise Lost 1.16). If Killeen succeeds in one thing with regard to Milton, it is to show that certainly none of this, in the strict rhetorical and poetic sense, was unattempted. Milton crashed this party late and then claimed it as his own. This book, despite the risk of dizziness and vertigo, should be read. It is an important work of impressive scholarship and brilliant critical insight. Not all might warm to Killeen's style, which precisely mirrors his subject in being at times overdetermined. Like a mystic or natural philosopher on the cusp of some impossible discovery, Killeen heaps adjectives and metaphors in his attempt to illuminate the very same mode of poetics he comes to adopt. The effect, however, is rarely excessive and always charming, whether it is in the book's many neologisms or striking images, like that of seventeenth-century prophets like Trapnel “rattling [the] bars” (22) of Scripture, or speaking of the “connective tissue” of Milton's threads of prolepsis and recollection in Paradise Lost as “a cat's cradle stringing together the devils and fallen humanity” (185). Similarly, the book's occasional evasion of hard arguments and conclusive findings traces its apparent hesitancy to the apophatic tradition itself, where, speaking for example of Milton's vision of the devils' recreational ground in hell, Killeen alerts us that there is “also a hermeneutic sublime here, in its sheer uninterpretable character” (189). One wants to shout out, in the manner of the ancient Skeptics, that this too amounts to an interpretation, but the paradox in this case is a rhetorical sleight of hand. Killeen's interpretive agency is best reflected in his ability to illuminate the grammar of apophasis across these diverse and fascinating texts and in this lies the book's singular triumph, both as an important intellectual and cultural history and as first-rate literary criticism.