The Shadow of God is a magisterial achievement. In that vein, readers may find it especially opportune that this is a book about the concept of immortality—though, in line with the more dynamic picture it presents of our ideas about immortality in shifting cultural landscapes, I make the more modest, though no less impressive, suggestion that this book will stay with students of German Idealism and of political theory at large for a very long time to come.

Among the book’s many achievements, one stands out as especially striking. The Shadow of God succeeds in bringing to life the worlds of Kant, Hegel, and their contemporaries in all their strangeness. In taking their concerns seriously—however remote they may seem from ours—The Shadow of God allows us to see where these authors were coming from, to sympathize with their problems and their solutions, all the while being firm about the differences between their moral commitments and ours. For instance, to cite an important theme of the book, the seeming vindictiveness of Kant’s infamous insistence that “the last murderer would first have to be executed” even in the event of the dissolution of society is not just an uncomfortable minor detail in the writings of an otherwise admirable philosopher (112). For Michael Rosen, it is in fact a central feature, stemming from a particular set of theological commitments about the justice of God that we may no longer share, but without which it would be impossible to get Kant right. Ignoring these alien and awkward aspects of where Kant is coming from has led many brilliant readers of Kant to get him wrong, and to help establish the conveniently watered-down, agreeable portrait of him we have come to inherit.

One of the consequences of the remarkable balance Rosen achieves—the balance between taking the worldviews of his subjects seriously while also being clear about their distance from ours—is that it suggests a compelling, and rather unusual, picture of large-scale cultural change, and of the place of philosophy in it. This is a picture in which there are different philosophical “commitments,” or what Rosen calls doxai, organizing and orienting the belief systems and worldviews of humans throughout history, with different doxai weaving in and out of the foreground, some continuous and some discontinuous. Philosophy, in this sense, can accordingly be understood as “the conflict of doxai” (21, 244). In doing the history of philosophy, we can also begin to think about the relationship between “our” contemporary concerns and the worldviews of our subjects in these terms. In the case of Kant’s bloodthirsty obsession with executing murderers—or any other feature of the philosophies of historical authors with which we might disagree—we can, at the very least, as Rosen suggests, “uncover and draw attention to the earlier doxai that are at work” (252).

The Shadow of God puts one particular doxa under scrutiny: the doxa of personal immortality, which undergoes a critical transformation as it is taken up by Kant, Hegel, and their successors. But the process through which this doxa gets transformed into what Rosen terms the doxa of historical immortality is one that unearths and dynamically interacts with a thick tangle of other important doxai—say, about what freedom looks like (248–49), about the nature of God and the world he created (251). At one point, Rosen describes the complex network of doxai in culture as a tapestry, whose threads run and are connected in different ways (256). Elsewhere, he invites his readers to visualize certain doxai being “diffused . . . across the sea-floor and becom[ing] an accepted part of the broader culture” while others are “contested in the foreground” (252); in a memorable image, he presents the active contestation of doxai by a generation of thinkers in terms of a “turning of the tide” (251).

I am very much convinced by this dynamic picture of culture and philosophy, in part because—as Rosen points out—it avoids the sense we get in thinkers ranging from Hegel to Jürgen Habermas that there is a single directional path by which societies, or at least “Western” society, becomes modern. And if Rosen has been explicit in advertising the subtle ways in which his thinking bears the marks of Hans Blumenberg’s influence over the years,Footnote ¹ I hope I am right in thinking that the model of cultural change he has given us is also a Blumenberg-friendly one—in which thinkers and authors exercise a great deal of agency as they rework, or “work on,” the threads of culture and thick conceptual vocabulary they have inherited.Footnote ²

I want to invite Rosen to elaborate on this model of cultural change. First, at the level of terminology, he distinguishes his use of doxa from that of Pierre Bourdieu (18), if I understood correctly, because he takes doxai to operate not only in the background but also in the foreground of our worldviews.Footnote ³ In this and other ways I take it that Rosen means for doxa to be a deliberately expansive term. All the same, this leaves open the question of what a doxa is and is not. For instance, it appears that Rosen arrived at doxa after many years of thinking about ideology, as he did in On Voluntary Servitude.Footnote ⁴ What was the reason for that shift, and what is the relationship between doxa and “ideology”? What is the relationship between doxa and other cognate concepts like the “social imaginary”—a term Rosen also at times seems to distance himself from (238)—or aspects of the “lifeworld”?

Second, Rosen could also provide a sense of scale, or the relative importance, of the particular doxa of personal—and later historical—immortality in the larger tapestry of doxai in the worlds of his subjects. Scholars of Plato’s Forms are often interested in questions like whether there can be a Form for trivial things. In a similiar vein, is it possible to estimate how many doxai there are in an individual’s worldview?

Finally, I want to ask about the kind of secularization story we get from the transformation of one originally religious doxa about immortality as it interacts with a network of other doxai—some religious, like divine benevolence, and some not in and of themselves particularly religious, like freedom as self-determination. Lay political theorists can often have a stereotypical impression of Kant as an eminently sensible juristic thinker, and Hegel, alongside contemporaries like Schelling and Schleiermacher, as idiosyncratic mystics with deeply religious backgrounds. One of the book’s achievements is to rescue Kant from this sort of impression—and, more subtly, to bring out the ways in which the more mystical features of the philosophies of some of these later German Idealists can be thought of as a Spinozan rather than a properly Christian legacy. Still, the story of secularization presented in The Shadow of God is one where the direction of comparative religiosity points the other way from what our stereotypes about these authors suggest, at least in this one very specific respect. It is a story that begins with a decidedly not secular, but all the same secularizing, Kant, whose project gets taken up and continued by Hegel, who delivers a kind of nail in the coffin of the doxa of immortality as a specifically religious idea.

What, then, about all the other ways in which Hegel and some of his contemporaries still appear so much more religious than Kant? Is this a situation where the secularization of one religious doxa—its passage from heaven to history—does not set off equivalent secularizations of others, or even sets off reactions going the other way in other doxai as thinkers scramble to grapple with the consequences of such a transformation? And what does that tell us about secularization at large? Have theorists of secularization been wrong to assume that the various doxai at play in the secularizing process all more or less change together in the same direction?