Pierre-Jean-George Cabanis (1757–1808), famous during his lifetime for being Mirabeau’s physician, recounted in his Journal de la maladie et de la mort de Mirabeau l’aîné the details of the great orator’s last illness and death between 28 March and 2 April 1791, including evidence of devastated Parisians weeping at the news. After Mirabeau, Cabanis continued to be involved in politics, hiding Condorcet when the philosopher faced the guillotine, and providing him with the poison that ultimately allowed him to take his own life. The third giant in Cabanis’s life was Bonaparte. As a deputy in the Council of Five Hundred and a conspirator, Cabanis welcomed the coup of 18–19 Brumaire (9–10 November 1799) and proclaimed the new regime both to have saved the republic and to be altogether legitimate. With fellow members of the Auteuil salon of the widowed Madame Helvétius, Cabanis embraced Bonaparte and the new Constitution of the Year VIII. Mariana Saad’s clearly written and elegant book about Cabanis is the first to do justice to the entire œuvre of this medical, moral and political thinker. Although its focal point is the vast and pathbreaking Rapports du physique et du moral de l’homme (1802), it takes all of Cabanis’ writings into account, dealing with the ‘epistemological foundations of his thought’ which directed his life and work (p. 20).

Cabanis considered medicine, politics, political economy and morals as a single science, derived from the truths of human nature and capable of influencing corrupt or inspiring moral behaviour through laws that expressed and promoted human wellbeing. In his 1790 pamphlet, Observations sur les hôpitaux, he condemned ‘social inequalities’ as being the product of ‘bad laws’ (p. 24). Cabanis was committed to reform; if laws were tied to the new science of manipulating human actions, the result would be peace and happiness. In 1795 Cabanis was involved in the creation of the École normale, the institution intended to put an end to the Revolution, as Dominique Joseph Garat put it (p. 27). The next year Cabanis presented three mémoires to the world, the Considérations générales sur l’étude de l’homme, et sur les rapports de son organisation physique avec ses facultés intellectuelles et morales in January, Histoire physiologique des sensations in July and Suite de l’histoire physiologique des sensations in August. In these texts, that were later to form key sections of the Rapports, Cabanis professed his conviction that the study of man must aim at the ‘entirety of human knowledge’ in order to progress towards the ‘political goal’ which was the ‘liberation of human race’ (p. 28). What this specifically entailed is the theme of Saad’s book, and copiously illustrated.

Saad presents Cabanis as sharing his friend Antoine Destutt de Tracy’s political goals and respect for Condillac, but having a distinctive theoretical approach to the problems of the day. Saad argues that Martin Staum, in his well known work, did less than justice to Cabanis by lumping him together with other idéologues and underplaying his intellectual originality in consequence. If Destutt de Tracy studied the ‘operations of the intelligence’, Cabanis approached the ‘functions of the mind’ from the field of physiology (p. 33). Cabanis was not uncritical of his intellectual master Condillac. He sought to expand Condillac’s understanding of man by introducing ‘sensibility without sensations’, which was, in Saad’s words, ‘one of the most original contributions of Cabanis to medical and philosophical thought’ (p. 55).

Cabanis’ studies on mind–body relations, language, heat, brain, madness, i.e. his entire conception of physiology, was greatly indebted to Hippocrates’ conception of equilibrium and balance. Balance was healthiness. Imbalance was illness. Imbalance in the body translated into problems in the mind. In the Rapports Cabanis asserted that ‘the moral is nothing more than the physical’ (p. 40). Health depended not on ‘temperance’ but on ‘equilibrium’. Bodily imbalance would lead to mental imbalance and consequently to disease. The quickest road to disease was ‘excess’ (p. 50). To this physiology were added the linguistic, cultural, social, political and geographical elements which would then circumscribe and define human health, and which could be contrasted with states of imbalance, illness and political extremism.

For Cabanis, as Saad reveals, madness was a social disease emanating from social imbalance. Crime was therefore a social disease, a madness inflicted on individuals by the improper form of society. This perspective led Cababis to argue that ‘poverty is, in general, the work of social institutions’ (p. 198). A society of ‘disharmony’ such as ‘the France under the Old Regime’ generated ‘disorder’ (p. 190). The French Revolution was a ‘paroxysmal moment that must destroy a disharmony’ (pp. 216–217). In turn, the coup of 18 Brumaire was necessary to dispose of the ‘agitations and disorders’ that had ‘characterized democracy to this day’ (p. 208). Those who rallied to Sieyès and to Bonaparte, the first two consuls of the new regime, were to be hailed as doctors of the political body who were exorcising excess and restoring equilibrium.

Saad’s meticulous reconstruction of Cabanis’s thought underlines the importance of liberty to happiness (p. 229), of early education for forming ‘equal, patriotic and free’ children (p. 234) and the capability of the human race for ‘infinite perfectibility’ (p. 240). To him it seemed that there was a ‘secret force’ in this world that led to a state of ‘order’ (p. 265). A society of free and industrious citizens could live in perfectly balanced health both in body and in mind, enjoying the ‘equality of means’ and the ‘equality of rights’ (p. 278). This force of order always progressed towards the ‘generalisation’ of equality and industry (p. 269). As such, Cabanis never lost faith in the Revolution as a project to improve humanity. While the transition mechanism to his ultimate goal did change from democracy to dictatorship, the vision was always alive for Cabanis. The great achievement of Saad’s book is to reveal the full extent of this vision of a perfected world.