To what extent does love involve making sacrifices for a lover? Thomas Lennon's Sacrifice and Self-Interest offers an important contribution to this debate by exploring how it emerged among seventeenth-century Cartesians, who disagreed about the essential nature of human beings’ love for God—pure love. On one side were Quietists, who claimed the purity of humanity's love for God was corrupted by self-interest. Opposing them were French followers of the Dutch theologian, Cornelius Jansen, who insisted pure love was beyond reach of fallen humanity.

Most literature on pure love centers on the French aristocratic nun, Jeanne Guyon, whose claims to divine inspiration provoked a dispute between her kinsman, François Fénelon, bishop of Cambrai, and Jacques-Bénigne Bossuet, bishop of Meaux. The French Church condemned her, but Guyon's writings became popular among British and American Protestants, and continue to excite devotion, and academic interest. Scholars have read the “Quietist controversy” from perspectives of literature, gender, and the history of spirituality. In this category, divisions between Quietist and Jansenist become irrelevant: both defended an almost-Calvinist interior piety that attracted Protestants. Lennon is the first to place the debate into its longer-term French context. This allows him to show pure love was a philosophical problem. Lennon argues that the debate concerned human volition. The libertarian position of the sixteenth-century Spanish scholastic, Luis de Molina, was popular in France until 1640, when Jansen published the Augustinus, which claimed free will and divine grace were compatible. Lennon shows Jansen's text influenced leading French thinkers, including Descartes, Malebranche, and Bousset. Quietism was condemned primarily for its Molinism.

Lennon's first two chapters introduce the Quietist understanding of pure love. To purify love meant abandoning self-interest. This required lovers to make a literal sacrifice, killing their selves. Their sacrifice rested on the “Impossible Supposition”: even if God damned just those who love him, he should still be loved. This raised an epistemological question: how could one know one loved God? Love was less than pure when its consequences became so terrible that the lover relinquished it. The “Impossible Supposition” was condemned by opponents who claimed it implied an unloving God. Lennon's second chapter shows these criticisms failed to grasp its logic. Quietists believed God damned nobody who loved him, but everyone should act as if he did. In chapter 3, Lennon shows the Supposition was the defining point of Quietism, widely held before Jansen. The person usually associated with Quietism—Jeanne Guyon—did not, and so she was not a Quietist.

Guyon's Quietist supporter, Fénelon, distinguished five steps one had to take between love of self and love of God. At the highest level, indifference, there was no self mixed in. Chapter 4 shows “indifference” concerned free will. Lennon traces the concept to Molina, who argued grace was necessary for salvation, but everyone had it, so the difference between saved and damned was down to human freedom. The will was indifferent because every exercise of choice could have been different in the same circumstances. For Quietists, indifference named the state where souls were “ready to will, or not to will, to will for God all that he wills, and never to will for itself not indicated by God's will” (108, quoting Fénelon).

Indifference was criticized by theologians, starting with Jansen, who associated it with Pelagianism. In his Augustinus, Jansen equated freedom with spontaneity: one had freedom only if one was bound by the terms of a promise previously made. Failure to act arose from one's failure to abide by that promise, not from one's freedom. Chapter 5 offers an account of the publication of Augustinus and provides lucid analysis of its argument. Lennon shows that Jansen's work set the standard for orthodoxy despite its density. Although both Fénelon and Bossuet claimed to follow Descartes, in chapter 6 Lennon harnesses textual and circumstantial evidence to show Descartes rejected Molinism in favor of Jansen's position.

Lennon next analyses the views of two participants in the Quietist controversy itself: Malebranche and Bossuet. Malebranche's devotional work is usually read alongside the Quietists’, and Bossuet's quarrel with them related to religious enthusiasm. Lennon shows these views are misguided. Malebranche entered the controversy after his work was used by the Quietist, François Lamy. Although Lamy started as Malebranche's closest disciple, Malebranche ended up defending the Jansenist views of Lamy's critics and was criticized by Fénelon in turn. In chapter 8, Lennon traces Bossuet's early concerns over Spanish Quietism, his arguments for the Jansenist's view of the will, and his promotion of their leader, Pasquier Quesnel. He shows that Bossuet remained a Jansenist even after the Church condemned Jansenism.

Chapter 9 argues the Bousset/Fénelon quarrel ended Catholic debates over human volition. The Church condemned the views of freedom and volition held by Descartes, the Jansenists, and the Quietists. This triple condemnation has cast a long shadow: Descartes’ modern reception has been “one of objection, with little by way of reply” (257). Jansenism has a problematic—and mostly academic—legacy within the French Church. Quietism has no Catholic legacy, but it did influence eighteenth-century Pietism, Enlightenment philosophy, and modern feminism.

Lennon claims “Quietism's conceptual scheme” is “more illuminating than it has been given credit for” (258). His final chapter presents a new case for pure love based on a total sacrifice of self-interest, including what his seventeenth-century subjects called “les derniers épreuves,” the last temptation (259), to feel pride when denying self-interest. Lennon argues that Quietist thought can ground an ethics that overcomes pride.

Combining close analysis of text and context, Lennon reveals the seventeenth-century concept of love differs in important ways from modern love, and deserves attention today. Scholars across the disciplines will gain from his unique contextualization of thinkers usually studied separately. There are problems: Lennon's normative argument could be better articulated. His philosophical language and occasionally awkward style will put some readers off. More could be said about Reformed theologians who engaged in similar disputes. Nevertheless, this is an important book that deserves a wide reception.