In my recent post on ‘Rethinking the idea of Christian Europe’,
I mentioned the debate between the Radical and the mainstream Enlightenment, a debate superbly explored by Jonathan Israel in his books Radical Enlightenment and Enlightenment Contested. The mainstream Enlightenment of Kant, Locke, Voltaire and Hume is the one of which we know and which provides the public face of the Enlightenment. But it was the Radical Enlightenment, shaped by lesser-known figures such as d’Holbach, Diderot, Condorcet and, in particular, Spinoza that provided the Enlightenment’s heart and soul.

The two Enlightenments divided on the question of whether reason reigned supreme in human affairs, as the radicals insisted, or whether reason had to be limited by faith and tradition – the view of the mainstream. Nowhere is this more evident, perhaps, than in the debate about toleration and freedom of expression. Here’s Jonathan Israel, from Radical Enlightenment, on Spinoza, Locke and the idea of toleration:

From Jonathan israel, Radical Enlightenment:
Spinoza, Locke and the Enlightenment Struggle for Toleration

Precisely as the warring moderate and radical wings of the Enlightenment produced rival and antagonistic theories of religion, science, morality, law and politics – the former extolling monarchical power, the latter democratic republicanism – so the two Enlightenments forged powerfully contrasting notions of toleration. On the one side was what came to be widely acknowledged as the acceptable face of toleration, a toleration rooted in the Dutch Arminians… and, following them,  John Locke. This was aptly characterised by the great Venetian theologian, Concina, in 1754, as essentially a ‘tollerantismo between the Christian Churches.’ Its core was freedom of worship and the peaceful coexistence of dissenting Churches alongside each national, or public, Church. What in their great majority eighteenth century writers were entirely unwilling to endorse was the other kind of toleration – the radicals’ demand for freedom of thought and expression, including the expression of ideas incompatible with the core tenets of revealed religion upheld by the Churches.

Locke’s theory is essentially a theological conception, asserting that it is for every individual not just to assume responsibility for seeking the salvation of his or her soul but… to perform openly that form of worship by which he or she seeks salvation. Locke’s toleration then revolves primarily around freedom of worship and theological discussion, placing little emphasis on freedom of thought, speech and persuasion beyond what relates to freedom of conscience…

By contrast the toleration of Spinoza… is essentially philosophical, republican and explicitly anti-theological. Freedom of thought and speech, designated libertas philosophandi by Spinoza, is the primary goal, while saving souls plays no part either in [his] advocacy of toleration or setting limits to toleration which, Spinoza concedes, may in a given society be advisable.

Precisely because it is a theological conception, Locke’s toleration is grudging, on doctrinal grounds, in according toleration to some groups and emphatic in denying toleration to others. In Locke three limitations on toleration are especially evident. First, his tolerance being what has been called a ‘privilege’ or ‘immunity’ from the form of worship otherwise generally prescribe din England by Crown and Parliament or mutatis mutandis by sovereign authority in other lands, it can only unequivocally pertain to those who adhere to an organized, permitted congregation for which exception can be claimed, such as, in the English case, Protestant dissenters, Catholics, Jews and potentially Muslims…

Secondly, there is Locke’s well-known equivocation… regarding Catholics. The question whether they should be tolerated is left in doubt for Locke, because the secular authority is not obliged to permit Churches which claim an authority, such as that of the Pope, deemed by adherents to transcend that of the territorial sovereign and even be capable of nullifying it. A third major curtailment in Locke is the categorical exclusion of ‘atheists’, a broad and flexible category in contemporary parlance, which embraced non-providential deists and pantheists. Since they reject divine Providence, participate in no acknowledged form of worship, and do not seek to save their souls, by definition they are not entitled to toleration.  ‘Those are not at all to be tolerated’, insists Locke, ‘who deny the being of a God’, not least because ‘promises, covenants and oaths, which a re bonds of human society, can have no hold upon an atheist’. According to Locke, the ‘taking away of God but even in thought, dissolves all.’

By contrast, in Spinoza, freedom of worship, far from constituting the core of toleration, is very much a secondary question, a topic which he discusses only briefly and peripherally. For in Spinoza toleration has primarily to do with individual freedom, not a coexistence of Churches, and still less the freedom of ecclesiastical structures to increase their followings, expand their resources, and build up their educational establishments…

In the democratic republic of the radicals it is not therefore the aspiration of individuals for spiritual redemption which drives the push for toleration, as in Locke and the mainstream Enlightenment, but rather the quest for individual liberty, freedom of thought and freedom to publish ideas which may be ‘philosophical’ in the new sense coined by Spinoza and his followers, and later embraced by the English deists and the French philosophes, meaning rooted in systems of thought based on ‘natural reason’ and, consequently, incompatible with, and opposed to, the Churches’ theological conception of God, man and the universe…

By insisting that ‘the less freedom of judgement is granted to men the further are they removed from the most natural state and consequently the more repressive the regime’, Spinoza clears a much wider space for freedom of speech  and the press than is allocated by Locke’s or Rousseau’s toleration…  All attempts, admonishes Spinoza, to curb expression of views, and censure books, not only curtails legitimate freedom but endangers the State… At the close of the Tractatus Theologico-Politicus Spinoza concludes ‘that the state can pursue no safer course than regard piety and religion as consisting solely in charity and just dealing and that the right of the sovereign, both in the religious and secular spheres, should be restricted to men’s actions, with everyone being allowed to think what he wishes and say what he thinks.’

[Jonathan Israel, Radical Enlightenment: Philosophy and the Making of Modernity 1650-1750 (Oxford University Press, 2001), pp 265-270]