In Utilitarianism in the Age of Enlightenment, Niall O'Flaherty traces the development of theological utilitarianism in the eighteenth century, from Edmund Law to William Paley. As the subtitle of the book indicates, the greater part of the book is made up of a contextual investigation of Paley's utilitarianism. In framing his book against Frederick's Rosen's Classical Utilitarianism from Hume to Mill (2003), O'Flaherty restores Christian utilitarianism to its rightful historical prominence. Although Paley and Bentham were contemporaries, O'Flaherty shows that Paley's moral philosophy was more influential than Jeremy Bentham's in the late eighteenth and early nineteenth centuries. Paley's Principles of Moral and Political Philosophy, first published in 1785, remained a textbook at Cambridge University from 1787 until the 1840s. Bentham only started to have his presence felt in Cambridge in the 1820s. Charles Darwin wrote in his autobiography that reading Paley as an undergraduate ‘had been the only part of his academic studies at Cambridge that improved his mind’ (p. 126). O'Flaherty also opposes the view that Paley was the ‘theocratic’ and ‘conservative’ antipode to Bentham (p. 254). Religion was the foundation of Paley's moral and political philosophy, but his emphasis was on worldly affairs and utility in the here and now as the fulfilment of the divine plan and the way to salvation. He understood utility as the way to interpret God's wishes, and history for him was a progressive unfolding of God's benevolent will.

Utilitarianism in the Age of Enlightenment is indebted to J. C. D. Clark's revisionism in the 1980s, which, in the words of O'Flaherty, ‘restor[ed] religion to its central place in eighteenth-century political discourse’ (p. 171). Through the case study of Paley and other Christian utilitarians, O'Flaherty engages with the historiography of the meaning of ‘the Enlightenment’. The book presents an important rejection of John Robertson's definition of Enlightenment as the quest for betterment in this life rather than the next (in The Case for the Enlightenment, 2005), as well as earlier historians from Peter Gay to Jonathan Israel who equated Enlightenment with anti-religion. The Christian utilitarians studied by O'Flaherty were indeed concerned with this life as well as the next. Moreover, for Robertson, England, unlike Scotland, did not really have an Enlightenment before Bentham, Richard Price, Joseph Priestley, Mary Wollstonecraft and William Godwin later in the century. In the first part of the book, however, O'Flaherty shows that Cambridge divines such as Edmund Law and John Gay in the 1730s engaged with the thought of John Locke and Francis Hutcheson, and argued that increased knowledge contributed to the advancement of mankind. Promoting a spirit of enquiry, these Anglicans were committed to applying the scientific and experimental method to all areas of human affairs, including religion. ‘If Gay and Law were detached from Enlightenment intellectual culture … they certainly did not know it’, O'Flaherty writes (p. 56). The book thus adds to the historiography on the notion of an Anglican Enlightenment, developed by J. G. A. Pocock, Brian Young, and more recently William Bulman and Robert Ingram. At the same time, O'Flaherty takes issue with the second half of Pocock's description of England's Enlightenment as ‘clerical and conservative’. As O'Flaherty shows in his book, Paley was committed to gradual improvement – moral and political – and he had little reverence for antiquity as such.

O'Flaherty argues that the Christian utilitarians were as opposed to enthusiasm, excessive zeal and pompous ceremonialism as the religious sceptic David Hume. Abraham Tucker, for instance, was concerned with the rise of Methodism in the 1760s, and Paley did not share John Wesley's ‘hang-ups’ about sexuality. For Paley it was a basic biological drive. However, Paley's moral thought was ultimately an attempt to respond to the challenge of Hume, who had argued that religion created a state of anxiety which could corrupt morality. By contrast, Paley believed that religious sanctions helped motivate people to do good and promote utility in their everyday interactions. He considered it part of his brief to provide moral guidance which contributed to Christian expediency and general welfare. In the end, O'Flaherty argues that Paley was unsuccessful in responding to Hume's most devastating critiques of religious arguments in the posthumous Dialogues Concerning Natural Religion (p. 147), but Paley's own faith remained unshaken. Paley attributed Hume's extreme scepticism to ‘intellectual hedonism’ and his inability to be ‘content with common reason’ (p. 149).

In politics, on the other hand, Paley was a disciple of Hume rather than Locke. Drawing on Hume's essay ‘Of the First Principles of Government’, Paley argued that government was founded on opinion rather than social contract (pp. 180–1). Like Hume, Paley reserved a right to resistance for subjects in extreme cases. The ‘Glorious’ Revolution could be justified because the little blood it shed (NB, at least in England; Scotland and in particular Ireland were different) was a price worth paying for the gains made. But the similarities between Hume's and Paley's politics can be overemphasized. For instance, Paley had much to say about specific reforms, from tithe taxes to the slave trade (pp. 173–4). Indeed, Paley believed that the success of the American Revolution had been providentially arranged as a retribution for Britain's participation in the slave trade. He was, however, opposed to general reform of political representation – which was notoriously disproportionate in eighteenth-century Britain – since it was the expediency of the laws that mattered rather than the abstract ideal of equal representation. And, like Hume, he defended crown patronage and executive influence over the legislative, known as ‘corruption’ in eighteenth-century parlance, as Hume had done in Essays: Moral and Political (1741). In politics, Paley ultimately thought that it was consequences rather than private morality that mattered, and that human beings had to be taken as they are (pp. 214–15). O'Flaherty demonstrates convincingly that Paley had no qualms about lifting arguments from the ‘Enlightenment’ political science of the notorious ‘infidel’ Hume. At the very end of the book, O'Flaherty argues that Paley's adoption of aspects of Hume's political thought may have helped subvert the Scotsman's endeavour of liberating politics from religion. This is an intriguing point, even though it raises more questions than it answers (which is clearly the intention). Hume may have been somewhat eclipsed in the nineteenth century, partly due to his religious scepticism, but from the point of view of the twenty-first century West, it would be difficult to maintain that it is Hume rather than Paley who has been subverted. On a side note, this tells us that we need more historical research on the reception and afterlife of Hume's thought.

Paley's quest for general welfare fed into a commitment to helping the poor. Charity was for him the highest virtue. He supported wealth distribution and proposed a graduated income tax not unlike the one later suggested by Thomas Paine (p. 273). Unlike the latter, however, Paley was not interested in unsettling long-entrenched hierarchies. His approach was paternalist and emphatically not levelling. Private property was the foundation of civil society and the propertied class had a right and duty to rule the nation. But the same class also had a duty to care for the less fortunate.

Although Paley was interested in promoting the material improvement of the poor, he had little to say about social mobility. In the last chapter of the book, O'Flaherty turns to Thomas Malthus, who stressed the importance of aspiration (pp. 292–3). For Paley, population growth was a principal aim of politics because it would increase a country's net utility. Malthus, by contrast, argued that population growth risked outpacing the increase in food supply, and warned that such a prospect would have disastrous consequences for the poor in particular. Unlike Paley, he opposed the Elizabethan poor laws and systematic relief, because welfare provisions only contributed to higher food prices, earlier marriages, more procreation and increased misery all round. O'Flaherty shows that Paley eventually accepted Malthus's principle of population in his Natural Theology or Evidences of the Existence and Attributes of the Deity (1802), but as an argument for the further need of Christian paternalism and general improvement. Natural Theology in turn became the target of Malthus's second edition of his Essay on the Principle of Population, where he underlined the importance of moral and prudential restraint. Malthus did not abandon the principle of utility, but rather ‘recommend[ed] the adjustment of customary morality in accordance with expediency’ (p. 305). According to O'Flaherty, the lasting reputation of Malthus's Essay has meant that generations of readers have continued to encounter a form of theological utility. The brief episode on Malthus at the end of the book foreshadows O'Flaherty's next project, which, as we learn from the dustjacket, will be entitled Malthus and the Discovery of Poverty. Presumably, Adam Smith – who is only briefly mentioned in the Introduction to the present book, but whose importance for changing attitudes about poverty can hardly be too strongly emphasized – will play a greater role in O'Flaherty's next book, especially if it is going to look beyond explicitly religious thinkers. The impact of Malthus on Bentham and J. S. Mill would also be a line of enquiry worthy of further study.

Utilitarianism in the Age of Enlightenment is a finely written and well-researched book with very little to fault. As an extremely small point, when O'Flaherty refers to Edmund Burke's contentment with the absence of any neo-Deism in the 1790s, it is likely that Burke had the posthumous publication of Bolingbroke's Works (1754) in mind as the last hurrah of Deism – which Burke satirized in his Vindication of Natural Society (1756) – rather than the 1720s and 1730s (p. 133). Writing in the Reflections on the Revolution on France in 1790, Burke referred to someone ‘born in the last forty years’ when he rhetorically asked, ‘Who now reads Bolingbroke? Who ever read him through?’ Bolingbroke's controversial writings on religion had been written earlier but had not been published in his lifetime. This is why Samuel Johnson told James Boswell that Bolingbroke ‘was a scoundrel, and a coward: a scoundrel for charging a blunderbuss against religion and morality; a coward, because he had not resolution to fire it off himself, but left half a crown to a beggarly Scotchman [David Mallet], to draw the trigger after his death!’ This is nearly a negligible point, however.

One of the greatest achievements of the book is the way it considers political thought in both intellectual and political contexts, especially in part three. O'Flaherty demonstrates that he is well-read in the great parliamentary historians of the 1960s and 1970s, including Ian R. Christie, John Cannon and Leslie Mitchell. This provides a thicker context for Paley's political arguments, and it is a healthy antidote to much intellectual history, which is often written with only cursory references to political events and everyday politics. In summary, Utilitarianism in the Age of Enlightenment is a pathbreaking book and required reading for anyone interested in the history of utilitarianism, Enlightenment historiography and British eighteenth-century political thought.