Passions of the Soul

In the treatise Passions of the Soul (French: Les passions de l'âme), the last of Descartes' published work, completed in 1649 and dedicated to Queen Christina of Sweden, the author contributes to a long tradition of theorizing "the passions". The passions were experiences now commonly called emotions in the modern period, and had been a subject of debate among natural philosophers since the time of Plato.

Notable precursors to Descartes who articulated their own theories of the passions include St. Augustine, St. Thomas Aquinas and Thomas Hobbes.

In 1643 Descartes began a prolific written correspondence with Princess Elisabeth of Bohemia, in which he answered her moral questions, especially the nature of happiness, passions, and ethics. Passions of the Soul was written as a synthesis of this exchange.

Amélie Rorty asserts that the examination of the passions present in Descartes' work plays a significant role in illustrating the development of the perception of the cognitive mind in western society. According to her article “From Passions to Emotions and Sentiments,” Descartes’ need to reconcile the influence of the passions on otherwise rational beings marks a clear point in the advancement of human self-estimation, paralleling the increasingly rational-based scientific method.

In the context of the development of scientific thought in the seventeenth century which was abandoning the idea of the cosmos in favor of an open universe guided by inviolable laws of nature (see Alexandre Koyré), human actions no longer dependent on understanding the order and mechanism of the universe (as had been the philosophy of the Greeks), but instead on understanding the essential workings of nature.

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