<p>The study aims to explain the role of external causes in René Descartes’s (1594–1650) and Benedictus de Spinoza’s (1632–1677) accounts of the mastery of the passions. It consists in three parts: the mind-body union, the passions and their classification, and the mastery of the passions. </p><p>In the first part I argue that Descartes’s conception of the mind-body union consists in two elements: mind-body interaction and the experience of being one with the body. Spinoza rejects the first element because there cannot be psychophysical laws. He accepts the second element, but goes beyond Descartes, arguing that the mind and body are identical.</p><p>In the second part I discuss the classifications of the passions in the <i>Passions of the Soul</i> and the <i>Ethics</i> and compare them with the one Spinoza presents in the <i>Short Treatise</i>. I explain that <i>hilaritas</i> is an affect that expresses bodily equilibrium and makes it possible for the mind to be able think in a great many ways. Furthermore, I consider the principles of imagination that along with imitation and the striving to persevere provide a causal explanation for the necessary occurrence of the passions. </p><p>In the last part I argue that in Descartes the external conditions do not have a significant role in the mastery of the passions. For Spinoza, however, they are necessary. Commentators like Jonathan Bennett fail to see this. <i>Hilaritas</i> requires a diversity of sensual pleasures to occur. As Medea’s case shows, reason is not detached from Nature. Spinoza attempts to form a stronger human nature and to enable as many people as possible to think adequately. His recognition of the need for appropriate external conditions and a society in which ideas can be expressed freely allows him to present an ethics with a practical application, instead of another utopia or fiction.</p>

The study aims to explain the role of external causes in René Descartes’s (1594–1650) and Benedictus de Spinoza’s (1632–1677) accounts of the mastery of the passions. It consists in three parts: the mind-body union, the passions and their classification, and the mastery of the passions. In the first part I argue that Descartes’s conception of the mind-body union consists in two elements: mind-body interaction and the experience of being one with the body. Spinoza rejects the first element because there cannot be psychophysical laws. He accepts the second element, but goes beyond Descartes, arguing that the mind and body are identical. In the second part I discuss the classifications of the passions in the Passions of the Soul and the Ethics and compare them with the one Spinoza presents in the Short Treatise. I explain that hilaritas is an affect that expresses bodily equilibrium and makes it possible for the mind to be able think in a great many ways. Furthermore, I consider the principles of imagination that along with imitation and the striving to persevere provide a causal explanation for the necessary occurrence of the passions. In the last part I argue that in Descartes the external conditions do not have a significant role in the mastery of the passions. For Spinoza, however, they are necessary. Commentators like Jonathan Bennett fail to see this. Hilaritas requires a diversity of sensual pleasures to occur. As Medea’s case shows, reason is not detached from Nature. Spinoza attempts to form a stronger human nature and to enable as many people as possible to think adequately. His recognition of the need for appropriate external conditions and a society in which ideas can be expressed freely allows him to present an ethics with a practical application, instead of another utopia or fiction.