“What is it worth to remain in Augustine’s debt?” is the rhetorical question at the heart of this book (161). While it took Pentecost Barker, the central subject of the study, many years to reach an answer, Matthew Kadane signals from the narrative’s outset his position: Augustine’s doctrine of original sin and orthodox Christian faith are burdens not worth bearing – culpable, in Kadane’s view, for some of the Enlightenment’s enduring limitations (11–19), the foundations of absolutist regimes (6–11), and the roots of modernity’s persistent alignment with dehumanizing capitalist structures (13–17).

Barker, an eighteenth-century ship purser, wine merchant, and Presbyterian elder, is presented through two primary sources. The first is a spiritual diary from the early 1730s; the second, a series of letters exchanged with Unitarian minister Samuel Merivale in the late 1750s and early 1760s. Kadane reads the former as expressing Calvinist Puritan piety, including a strong commitment to the doctrine of original sin. The later correspondence reveals Barker’s eventual rejection of that doctrine, along with broader elements of traditional Christian orthodoxy. Kadane sees this shift as emblematic of a broader intellectual movement: the Enlightenment’s rejection of Augustinian anthropology and its embrace of a more optimistic account of human development.

Although Kadane consistently refers to “the Enlightenment” (notably using the definite article and capital “E”), he acknowledges diversity in its rejection of original sin. One path led to what he calls “anthro-pessimism”: a secularized variant of original sin retaining a negative view of human nature. Thinkers like Voltaire, Locke, Mandeville, and Smith fall into this trajectory. Though discarding Augustine’s theological categories, they still viewed the self as flawed and susceptible to selfishness, competition, and the need for constraint – insights Kadane argues supported political individualism and capitalist economics.

The other path exemplifies “anthro-optimism” – a more thorough repudiation of the Augustinian legacy (174). This view admitted moral failure but denied its inevitability. Human beings could, through reason and love, align with a universal rational principle, or “Nous,” and thereby overcome sin. Kadane places Rousseau here, but gives pride of place to the “protosocialist” vision of Étienne-Gabrielle Morelly (158).

From the perspective of anthro-optimists like Barker, Augustinians and Calvinists were dangerous – but secular anthro-pessimists, in Kadane’s analysis, were potentially worse. This pessimistic lineage extends to a troubling constellation of intellectual figures and political regimes, from the “throne and altar” conservatism of Bossuet and de Maistre to the ideologies of Carl Schmitt and the Nazis. For Kadane, the Enlightenment’s darkest legacies may arise not from the persistence of theological orthodoxy, but from its secularization. Even so, he offers moments of nuance. As he notes, theological–political alignments during events like the English Civil Wars and the French Revolution were complex: “Augustinians could be found, as easily as could Pelagians, among the rebellious or those otherwise threatening the status quo” (123). The historical question becomes not merely whether original sin was rejected, but how comprehensively – and by what means – it was left behind.

Kadane’s integration of microhistory and intellectual history is both commendable and illuminating. His portrayal of Barker’s transformation is careful and situated in broader philosophical and theological contexts. Yet greater theological precision would enhance the argument, particularly regarding original sin. Kadane introduces it early as the “Christian doctrine that said that human beings were depraved, ancestral sin was inescapable, and self-control was an illusion” (2). A later chapter summarizes the Roman Catholic view from the Council of Trent: “the first sin was committed by Adam, affects everyone, is transmitted by sex, demands infant baptism, and can be pardoned only through the grace of Christ” (23).

While perhaps useful as initial glosses, these accounts are partial and imprecise, limiting theological depth. Kadane does not engage distinctions between Catholic and Protestant views on the corruption of intellect and will, nor intra-Protestant debates over whether original sin involves imputed guilt in addition to corrupted nature. Moreover, the claim that the doctrine requires transmission “by sex” overlooks important nuances – such as the difference between sex and procreation. Many Protestants Kadane refers to held that original sin was communicated federally (via covenantal representation), not seminally (via biological transmission). These theological differences have significant implications for questions of metaphysics, epistemology, agency, and ethics.

The concept of grace is likewise underdeveloped. Its absence from the index is striking, and when it appears – for example, in discussions of baptism – it invites clarification. While Roman Catholics and many Lutherans teach that baptism removes original sin, most of the denominations associated with Kadane’s figures did not share this view. Their practice of infant baptism rested on a different theological logic (cf. 112). A fuller treatment of divine grace would deepen the analysis. Augustine, in Book I of De Doctrina Christiana, grounded his account of sin and salvation in love and divine charity, rejecting a love of self apart from love of God and neighbor. Calvin, in the Institutes (II.II), spoke of God’s grace enabling non-Christians to contribute meaningfully to the arts, sciences, and civil society. Neither denied humanity’s potential for growth, virtue, or pursuit of temporal goods – though they saw such achievements as ultimately dependent on divine grace.

In the preface, Kadane characterizes the work as both a microhistory and a contribution to intellectual history. As a microhistory, it is highly effective: the depiction of Barker’s evolving convictions is both nuanced and compelling. As intellectual history, however, the book occasionally departs from analysis and enters the realm of theological advocacy – most notably in its critique of original sin and endorsement of Enlightenment alternatives. Kadane’s methodology lends support to the concerns recently raised by Jonathan Clark, who argues that “the Enlightenment” functions more as a historiographical construct than as a coherent historical reality, and that its deployment often reveals more about the historian than the subject under study (The Enlightenment: An Idea and Its History, 2024). Even so, Kadane’s critique of anthro-pessimist secularizations remains cogent and well-argued. A more theologically attentive framework might further illuminate the potential relevance of Augustinian paradigms for contemporary reflections on human dignity, limitation, and renewal. Given Kadane’s evident sensitivity to complexity, he might even be open to unexpected convergences.