In many ways, we live enmeshed in Enlightenment values: societies can be asked to alter their behaviours on the basis of science to alleviate the spread of a virus, the consequences of which many will not have seen at first hand; complex protocols can be agreed to mitigate climate change, the science behind which has to be taken on trust by most. And yet such examples also show the limitations of reason: scientists themselves differ on what to do in response to the coronavirus, and beyond them lies a vast penumbra of misinformation masquerading as knowledge. The ability to decode such misinformation is beyond many citizens.

It is perhaps because we still live in the shadow of the Enlightenment that its ideas have in recent years given rise to a greater number of what we might call ‘doorstop books’ aimed at the general public than any intellectual movement in a comparable era has. Enter Ritchie Robertson, Taylor Professor of the German Language and Literature at the University of Oxford, with the boldly titled The Enlightenment. Robertson does not want to stake a claim for the immediate ‘relevance’ of the Enlightenment as a set of ideas prescribing how we should act today. His ambitions are the panoramic ones of the historian. He tries, and by and large succeeds, to show us the patterns of thought of the denizens of the 18th century in all their complexity and diversity, rather than attempting to dragoon the effusion of ideas in that era into a simple structure of ‘progressives versus reactionaries’.

What, then, is Robertson’s Enlightenment about and how does it differ from other recent versions? We can start to answer that question by looking at a section in the middle of the book addressing Samuel Richardson’s novel Clarissa (1748). The first thing to note is that Richardson’s book is discussed at all. Most conceptions of the Enlightenment focus on a rather narrow selection of philosophical texts, whereas Robertson’s range is far wider. Many of the great writers who regularly appear in the canon of the Enlightenment – such as Rousseau, Goethe and Diderot – were fascinated by Richardson’s novel and it was routinely read, debated and imitated across Europe. However forbidding we may now find Clarissa, it clearly spoke to its age and any attempt to understand the Enlightenment must address that fact.

Robertson’s interpretation of the Enlightenment is distinctive in three ways, each of which shows his attunement to the ‘Clarissa problem’. First, he devotes considerable space to the fact that the Enlightenment was almost never atheistic and indeed was often strongly religious. Any staging of the Enlightenment as a ‘pagan’ war against religion is misleading, as the strong fascination with the Christian message of Samuel Richardson’s novel makes clear. Secondly, Robertson is persuasive in unpicking the notion of the Enlightenment as ‘the age of reason’, if reason is taken as antithetical to emotion: Clarissa was devoured as a novel of ‘sentiment’ – of the passions and emotions. The Enlightenment perspective was perhaps best captured by David Hume when he stated that reason is the slave of the passions, such that the elevation of reason as an independent arbiter is a fantasy. Robertson’s third point is that the disparate strands of the Enlightenment were drawn together not by the pursuit of reason for its own sake, but by the pursuit of happiness (as his subtitle has it) via reason, political economy, utilitarian calculus and the like. One of the things that most exercised Richardson’s readers was the purported lack of a ‘happy ending’ for Clarissa Harlowe. Obviously for Richardson the example of a life led piously trumped the tragic circumstances of Clarissa’s death, but many readers wanted happiness in this world for the heroine (something Richardson had provided in an earlier novel, Pamela).

The overwhelming impression left by this book will be of the diversity and complexity of Enlightenment thought. Robertson’s range is encyclopedic. An insight into the sheer scope of his research comes from the wonderful index (indexing was an art that Enlightenment-era scholars themselves valued – as can been seen in Edward Gibbon’s The History of the Decline and Fall of the Roman Empire). ‘Masturbation’, for instance, is followed by ‘materialism’, and the Kantian phrase ‘disinterested pleasure’ is sandwiched between ‘diseases’ and ‘dissenters’. The Enlightenment is also inclusive in terms of gender, geography and race. Yet there is a certain tension at the heart of the book. On the one hand, Robertson strongly affirms that there was a coherent entity called ‘the Enlightenment’, worthy of capitalisation and the definite article. On the other hand, the welter of ideas discussed in The Enlightenment seems resistant to any such singular framing. The achievements of the age are undoubted, but the fissiparous tendencies of Enlightenment thought were surely stronger than Robertson at times acknowledges.

By not imposing the heavy hand of ‘relevance’ on the age of the Enlightenment, Robertson in fact makes its modern legacies all the more apparent. He exposes, for example, Hume’s attitudes to race with crushing directness, not in his own voice but via the words of Hume’s contemporaries Lord Monboddo and James Beattie. Likewise, the relevance in the present moment of Helvétius’s comment that ‘not a single cube of sugar arrives in Europe which is not stained with human blood’ scarcely needs emphasis. Robertson embodies the values of candour and civility for which the subjects of his book stood. He has written surely the best – by which I mean the most representative and selfless – single-volume study of the Enlightenment that we have. If you have space for only one of these recent doorstop histories on your shelves, make it this one.