In our everyday lives, we are surrounded by white-toothed smiles. We flash a shiny smile to show our politeness to our fellow man. Hollywood stars always pose for the camera with a huge smile that lets their planetary fame shine through, and politicians do not hesitate to present their ideas with a big smile in order to convey trust to the population, even when they know that they are consciously lying.

Although we usually consider smiling one of the most banal actions that a human can undertake, Colin Jones reminds us that it is a fatal error to look at this gesture as a mere physiological response, which has existed unchanged for six million years. What he proposes in his latest book is that we approach this facial expression quite differently, as a historical object which emerged in a particular place and time that corresponds, furthermore, to a context that he knows perfectly well: the society of mid-eighteenth-century Paris. Therefore The Smile Revolution may be regarded as an exercise inscribed within what contemporary scholars have agreed to call the history of emotions, a kind of history of the present that aims to explain how our current rules of feeling and expression have become what they are today.

Jones's starting point is Elisabeth-Louise Vigée Le Brun's self-portrait, a painting in which she represented herself with a toothsome smile while carrying her daughter Julie in her arms. Although the scene displayed in this oil on canvas seems to be conventional, its exhibition in autumn 1787 at the Paris Salon provoked a scandal because the critics considered that it reproduced a controversial smile that had no precedent in the history of art. This is why Jones's book seeks to give a response to the enigma of Vigée Le Brun's smile, understanding it as part of a larger affective revolution (which he has baptized the smile revolution) that would have important implications for the political revolution of 1789. He interprets this radical shift concerning the expression of feeling as the consequence of two major developments: the appearance of a new group of professionals who preferred to call themselves dentists in contrast to the tooth-pullers (les arracheurs de dents), and the rise of a cult of sensibility, which celebrated the smile of heroines in literary fiction, such as Richardson's Clarissa and Rousseau's Julie.

Chapter 1 decodes the cultural meaning of the smile and the closely related phenomenon of laughter, in relation to what the author calls ‘the Old Regime of Teeth’ (p. 16), by analogy with the absolute monarchy that ruled in France from the late fifteenth century to the late eighteenth. In Jones's view, Hyacinthe Rigaud's Louis XIV portrait perfectly represents the politics of emotional expression exerted from the royal court of Versailles, where no smile was permitted. This can be partly explained by the fact that the king was completely toothless, but also because of the negative social perception involved in the act of laughing, which was strongly associated with the plebeians, the buffoons, women and the insane. Our modern smile (le sourire) could not exist in such historical conditions, as it was just considered an epiphenomenon of a broader bodily event concerning the uses of the mouth, the laugh (le rire), whose meaning was more likely associated with emotions such as contempt and disdain.

Chapter 2 deals with the transition from Louis XIV's regime of facial control to the emergence of a new economy of feeling, in which Parisians would learn to bring tears to their eyes and to conjure up a smile on their face through imitation of the heroes of the late eighteenth-century theatre plays. Far from the rigid codes of expression prevailing in the royal court, Parisians would enjoy living in a distinct world of emotionality in which the smile would become a sign of sociability and, moreover, of the authenticity of the self that reinforced the optimistic account about human nature spread by the Enlightenment thinkers.

Something is required, however, to complete Jones's smile revolution, and this is the appearance of a professional group that responded to the demand of having a white-toothed smile, challenging the advent of sugar, coffee, tea, tobacco and chocolate in the Western diet. Chapters 3 and 4 focus on explaining how modern dentistry came into being in mid-eighteenth-century Paris, once the tooth-pullers were replaced by a new kind of dental surgeon dedicated to oral health care. The veritable signature of this Parisian dentist movement, which was led by personalities such as Pierre Fauchard, was the preservation of the teeth rather than their extraction when an infection occurred. This strict policy of tooth conservation gave dentists an international credibility, making of Paris ‘a proto-industry of smiles' as a result of the introduction of this ‘new facial technology grounded in forging individual identities' (p. 99) to the bourgeois public sphere.

While in Versailles things never seemed to change, as if ‘a kind of mental paralysis in the face of change was in play’ (p. 120), the population would welcome the fall of the Bastille with tears and smiles in the streets of Paris. Nevertheless, this moment of exuberant expression of emotionality would not last a long time. As explained in Chapter 5, the smile revolution was only a transient period which paved the way for the Reign of Terror, when radical Revolutionaries began to regard this gesture with suspicion as the last vestige of the douceur de vivre which characterized the Ancien Régime. Gothic tales of horror contributed to undermining the spread of the positive aura of the smile by creating a monstrous vision of the mouth during the Terror, which also came to be related to the series of revolutions that would shock nineteenth-century France.

That was how Parisians forgot Vigée Le Brun's smile, and came back to the Old Regime of the Teeth. In the last chapter, Jones elucidates the most important consequences of this oblivion, such as the disappearance of dentistry in nineteenth-century France. A proof of this decline is that Napoleon III's dentist was a North American practitioner, the famous Thomas Evan, whose expertise anticipated the cultural hegemony of white-toothed smiles that would be exerted throughout the twentieth century from the United States.

Jones concludes by pointing out that smiles seem today ‘as ubiquitous as ever’ (p. 183), and are widely accepted as having a place in our modern culture. Our contemporary love affair with the smile does not seem to be, however, unquestionable. While I am writing this review, media around the world announce that a million marchers are expected today to the take to the streets of Paris after the terrorist attack perpetrated against the satirical magazine Charlie Hebdo. Smiling and laughing are not as banal as we believe. Indeed, the interest of reading Colin Jones's book lies in showing that this apparently innocuous facial expression is a politically charged issue that has revealed throughout centuries the health of our civil liberties in the Western world.