Introduction

In antiquity psychology, as the science of the psyche (Greek for ‘‘soul’’), was a part of philosophy. Psychological problems (perception, emotions, behavior, etc.) were actually treated by various philosophical schools, which proposed different accounts depending on their different theories about the substance of the psyche (materialist or immaterial), its structure (either unitary or divided into rational and sensitive parts), and so on.

Besides philosophy, psychological topics were also treated by ancient medicine, which was interested in the study of sense-organs, psychopathology, and related issues. The medical approach to psychology differs from the philosophical one in giving priority to the somatic causes of the phenomena in question; by doing so, it assumes an influence of the human body upon psychic life. This approach is present in the Hippocratic treatises: the principal thesis of De morbo sacro (On sacred disease) is that epilepsy and mental disorders are caused by humoral pathologies of the brain (3, 3.366 Littre), and in the Aphorisms (6.23, 4.568 Littre) we read that fear (phobos) and sadness (dystymia) are symptoms of melancholia (the disease caused by black bile), so that an organic fluid, the black bile itself, has an influence upon emotions.

Throughout antiquity the philosophical and the medical approach coexisted as different interpreting codes for psychic phenomena, but the boundaries between the two fields were different in different times and places. The Peripatetic school was inclined to acknowledge the influence of the body on the psychic life, as revealed by its interest in physiognomics, the theory that individual characters are recognizable from somatic features (Ps.-Aristotle Physiognomies 1, 805a), or by its speculations about the melancholia of poets, statesmen, and so on, according to which they are all affected by black bile (Ps.-Aristotle Problems 30, 953a). The Stoic school, on the other hand, made use of medical language to describe the

Features of the psyche and called the passions ‘‘diseases of the soul,’’ to be cured by means of reason and philosophy (e. g., Diogenes Laertius 7.110-16; Cicero, Tusculan Disputations 4.11-21). The Stoics were obviously aware that diseases such as melancholia could involve the use of reason (Diogenes Laertius 7.127), but they generally admitted only a limited number of such instances and explained human behavior from the rational and moral perspective. Posidonius, trying to delimit more precisely the boundaries between the two fields, distinguished four types of diseases: diseases of the body, diseases of the soul, diseases that ‘‘do not belong to the soul but are physical with mental effects’’ (like melancholia), and those that ‘‘do not belong to the body but are mental with physical effects’’ (fragment 154 Kidd).

An example of this last type of disease is ‘‘love sickness.’’ It is the object of an anecdote that is known in several versions with different protagonists. In one of the versions the famous physician Erasistratos (third century bc) is called to cure the sickness of Antiochos II Soter, son of Seleucus, king of Syria. From pulsation and other physical symptoms, Erasistratos realizes that Antiochos was not suffering from a somatic disease but was in love with Stratonike, his stepmother (Plutarch Life of Demosthenes 38).

This anecdote shows that the boundary between diseases of the body and diseases of the soul was well fixed on practical and professional grounds. On theoretical grounds, however, apart from Posidonius’ classification, the connection remained unresolved, as shown by Galen’s ambiguous position. In his work entitled Quod animi mores corporis temperamenta sequuntur (That the faculties of the soul follow the temperaments of the body, 14.767-822 Kuhn), he points out the influence exerted by the body upon the soul: the body is not involved in mental disorders only, but it also affects man’s character and the whole of his psychic life. In his subsequent work De animi cuiuslibet affectuum dignotione et curatione (The diagnosis and cure of the soul’s passions and errors, 5.1-57 Kuhn), however, Galen adopts both a philosophical point of view and a philosophical language, explaining the passions as diseases of the soul and ascribing to philosophy the function of paidagogia (pedagogy), as in the Stoic tradition (Stok 1996: 2371-5).

The two approaches we have found in antiquity are the roots of the modern mind-body dualism, as Karl Popper demonstrated by pointing out the Hippocratic De morbo sacro as its prototype (Eccles and Popper 1977: 161). Moreover, both approaches continued throughout the Middle Ages and into modern times. The philosophical approach was inherited, through late antiquity, by Christian thought, in which the concept of the soul acquired religious and theological implications. In its turn, modern psychology, from Descartes on, also derives from the philosophical tradition. The medical approach, on the other hand, continued in the Galenism of the late Middle Ages and Renaissance.

In modern times, too, the boundaries between medicine and psychology experienced changes and modifications. In the following sections we shall explore some episodes of this history in which the reception of ancient authors or topics demonstrates some importance.