Bayle invites us to reflect on the psychological effects of conformity on the dissenter himself, forced to violate his conscience, as well as the counter-intuitive implications of this infringement. Bayle suggests that infringements on conscience are experienced as deep violations by the dissenter, arguably just as unsettling as more violent forms of discipline and coercion. The experience of conforming to the state religion does not merely corrode mutual understanding among citizens but asks individuals to endure the taxing experience of suppressing and violating their consciences. Hypocritical conformity is not merely a trivial demand with little consequence for their integrity, as advocates of religious persecution insist, but a deeply felt violation that reverberates even long after the act of conformity is finished. Even more discerningly, Bayle recognizes that hypocritical conformity exacerbates conscientious fervor. Hypocritical conformity does not merely fail to inspire genuine conversion; it also radicalizes dissenters and urges them to be even more committed to their conscience. In an attempt to transform dissenters through hypocritical conformity, the state risks emboldening dissenters even further and inciting backlash against the state.

This book argues that liberty of conscience remains a crucial freedom worth protecting, because safeguarding it prevents political, social, and psychological threats to freedom. Influential early modern theorists of toleration, John Milton, Thomas Hobbes, Baruch Spinoza, and Pierre Bayle, I show, defend liberty of conscience by stressing the unanticipated repercussions of conformity. By recovering the intellectual origins of liberty of conscience in early modern politics and situating influential theorists of toleration in overlooked historical debates on religious dissimulation and hypocritical conformity, I demonstrate that infringements on conscience risk impeding political engagement, eroding civic trust, and inciting religious fanaticism. While this is a book about freedom, it is also a book about threats to freedom, specifically conformity, hypocrisy, and persecution. It considers the social, psychological, and political harms done by political refusals to tolerate religious differences and allow individuals to practice their religion freely in accordance with the dictates of conscience. By returning to a historical context in which liberty of conscience was not granted to religious dissenters –but rather actively denied – this book foregrounds Bayle’s argument that coercing conscience exacerbates religious fervor and inflicts significant psychological harm on dissenters, thereby undermining the goal of cultivating social cohesion in politics. In controversies on the politics of conscience, I suggest that we acknowledge that refusals to tolerate claims of conscience – while perhaps well-grounded in democratic laws and norms – might exacerbate conscientious fervor and empower resentment against the state. This Baylean intuition does not necessarily tell us where to draw the limits of toleration – what should be tolerated and what goes beyond the pale – but it does tell us something about how to approach invocations of conscience and what to expect when we deem something intolerable.

This chapter returns to the start of Bayle’s publishing career, and the famous argument for the possibility of virtuous atheism in the Pensées diverses. Bayle’s sources and modes of argumentation are identified. Ultimately, the work was a relatively trivial piece of haute vulgarisation; to the extent that the book had an underlying message, it was to outline an anti-Pelagian anthropology. The book proved entirely uncontroversial until it was incorporated into the anti-Bayle campaign waged by Jurieu in the early 1690s. Only at this point did Bayle come up with the elaborate historicisation already discussed in II.1, which also served to expand greatly the canon of (moral) ancient and Asian atheists. But this argument also served another purpose: to further elaborate Bayle’s case for toleration, based on the rights of the errant conscience. This involved Bayle in the theological controversy over ‘philosophic sin’ that had been stirred up by Antoine Arnauld. It led him to develop his mature position. Philosophy had historically been valuable in morality, but disastrous when it came to conceptualising the divine. Christianity had resolved the situation by providing solutions to otherwise insoluble theological problems via its doctrine of creation ex nihilo by a transcendent creator deity (rather than a metaphysical first principle), and by supplying the common people with a set of moral doctrines clearer than those of any philosopher.

This chapter outlines Bayle’s mature vision of the best worldview that could be produced by a perfectly rational human mind, as advanced especially in some of the most famous articles in the Dictionnaire and in the Continuation des Pensées Diverses. It is shown that Bayle owed a huge debt to the Gassendi and his successors on this score, taking the most rational philosophy available to a pagan to be an atheistic monism in which the first principle was immanent in the world. Bayle’s sources were exactly those identified in I.3 as following Gassendi on this matter (Thomasius, Bernier, Parker), as well as the anti-Jesuit accounts of Chinese and Japanese religion. But for Bayle the philolosophico-theological payoff of this genealogical vision was not recourse to Gassendi’s own philosophy, but rather to Malebranche’s occasionalism, which for Bayle was the only possible ‘Christian philosophy’. This elaborate historicisation therefore allowed Bayle to make a natural-theological argument, which was deployed against Spinoza among others. But at the same time, Bayle also acknowledged the explanatory limits of Cartesian occasionalism, above all when it came to issues stemming from the incomprehensibility of mind-body interaction: the ‘place’ of immaterial substances and animal rationality. This position was neither scepticism nor fideism, but an argument about the practical limits of philosophy.

This chapter introduces Part II, on Pierre Bayle. It provides an intellectual-biographical account of Bayle’s career, emphasising both his deep immersion in circles of Reformed scholars and theologians, and the reactive dimension of his writing, which were almost always shaped by his most recent reading. It urges caution about trying to find a coherent system in all of Bayle’s writings, and instead presents a framework for a developmental account of his thought. It also introduces the historiographical debate about Bayle, and the so-called ‘Bayle enigma’. It suggests that that enigma can be dissolved even if we carefully place Bayle in his own context, and avoid misleading categories such as ‘scepticism’ and ‘fideism’.

The most famous subject on which Bayle has been claimed to be either a fideist or an atheist is his discussion of the problem of evil in the ‘Manichean’ articles of the Dictionnaire and in subsequent writings. This chapter contextualises those writings so as to outline Bayle’s sources, and to show that he was engaging in a tripartite polemic about the theological doctrine of predestination. From Gassendi, Bernier, and others Bayle had learnt to argue that the problem of evil had no full solution: a purely rational (pagan) philosophy led to a deterministic fatalism. Gassendi, Bernier and others had used this point to insist on the necessity of adopting a Molinist doctrine of free will. Bayle argued the opposite: while it was indeed impossible to reconcile predestination and free will, history had shown that this did not lead to moral laxness. At the same time, the predestinarian position was more rational than the Molinist one, since it best accorded with the idea of unitary, omnipotent deity (which all sides agreed was rational). It is shown that Bayle adopted this argument from several Reformed theologians with whose writings he was well familiar: his teachers Louis Tronchin and Francis Turretin, and above all Jacques Abbadie and his then-friend Pierre Jurieu. But for Bayle this conclusion also had a political pay-off that put him at odds with Jurieu: that the difficulties of theological doctrine should lead to mutual toleration of differing opinions, rather than to a destabilising odium theologicum.

This chapter expands the conclusions of II.2 to explore how Bayle thought it was still rational to be a Protestant, even if the mysteries of faith were beyond the grasp of reason. Bayle had been deeply influenced by certain Catholic theologians, above all Pierre Nicole and Antoine Arnauld, who had argued for the incomprehensibility of dogma, and the need to adopt a positive rather than a philosophical method in theology. But while for them this led to an emphasis on the authority of the Catholic Church, Bayle deployed the argument to defend (Reformed) Protestantism. For him, even if one acknowledged the incomprehensibility of the mysteries, there were still rational grounds to choose to believe some mysteries (e.g. predestination) over others (e.g. the Real Presence in the Eucharist). These reasons were grounded in historical testimony, approached probabilistically. In turn, we can completely revise of our understanding of Bayle’s debate with the so-called ‘rationaux’ (above all Jean Le Clerc and Isaac Jacquelot). Bayle was no more or less fideist than his opponents, who were no more ‘rationalist’ than him; indeed, Bayle’s position was directly influenced by Le Clerc. The debate between them was in reality a confessional one, with both sides accusing the other of rationalism. Le Clerc was arguing that Bayle was a rationalist beholden to philosophical determinism, and that a non-philosophical biblicism revealed the truths of Christianity – which happened to be Arminian. Bayle was arguing that Le Clerc was a philosophical rationalist beholden to the idol free will, and that a non-philosophical biblicism revealed the truths of Christianity – which happened to be Reformed.

Edward Andrew discusses Pierre Bayle, who held that conscience was the “voice of God,” but that humans can still err. Enlightenment thinkers increasingly insisted that social approval, not God’s voice, guided conscience. Thus, conscience became not about certainty concerning the right course of action, but rather about alignment with social forces that might create stability. Bayle maintained that conscience was a faculty of the person, although subject to error. This distinguished him from Locke, who referenced conscience in his political writings. However, in his Essay concerning Human Understanding, Locke asserted that conscience was only one’s abiding beliefs. Bayle, however, proposed that conscience was the development of applications of natural law and Scripture. Harold Schulweis and Harold Berman are conversation partners for Bayle. Schulweis sees conscience as a force of judgment outside law. Morality is not fixed; rather, the person with an active conscience constantly recalibrates her actions and judges the right thing to do. Berman, however, thought conscience as a force beside law, like a jury that renders its judgment about the right decision under the circumstances.