جنون در طب و فلسفۀ ابن‌سینا

Madness as a medical, social, literary, and philosophical issue has always been the focus of thinkers. Avicenna, as a philosopher-physician, investigated and analyzed this issue in two medical (physical) and philosophical (metaphysical) areas. In the framework of medical science, based on the mechanism of human temperament, he analyzes why madness occurs. However, temperamental disorders are the starting point of Avicenna’s philosophical explanation of melancholic illusions, and Avicenna’s innovation was sought in this field. Temperament disorder leads to a disorder in the functioning of the rūh-i bukhārī, and this leads to a disorder in the relationship between the rational soul (nafs-i nāteqah) and the body. Through this disorder, a disconnection is created between the mental forms of the madmen and reality, because the imaginative (mukhayyalah) faculty as the generator of imaginary forms, and the common sense (ḥiss al-mushtarak) as the home of tangible and imaginary forms due to the disconnection or weakening of their connection with the intellectual faculty, deprives the insane person of this possibility to separate the illusive forms from the real. The main problem that this research delves into is to explain the phenomenon of madness from Avicenna’s point of view with a descriptive-analytical approach, and it is an attempt to provide a detailed and comprehensive presentation of his point of view based on medical and philosophical foundations.
 
Introduction
Avicenna, the greatest philosopher of the Islamic world, is among the thinkers who looked at the issue of madness; however, his thoughts on this issue have not been comprehensively and accurately analyzed. The few works that have dealt with this issue have limited themselves to the experimental and medical approach. Avicenna’s medicine is deeply influenced by his philosophy; therefore, the foundations of his philosophy have a direct impact on this issue. Avicenna is influenced by physicians such as Hippocrates and Galen in the issue of mental diseases; nevertheless, with a philosophical approach, and in an epistemological way, which is derived from his anthropological foundations, he analyzes the mechanism of madness (and mental illnesses), something that was previously not been discussed among philosophers and physicians. Discovering and expressing this innovation of Avicenna is the innovation of this research.
Medical explanation (physical analysis)
The Humoral Theory of Hippocrates was a completely naturalistic framework for the explanation and treatment of diseases and led physicians to avoid supernatural explanations of earthly phenomena. In the framework of the theory of humors, Avicenna points out several factors that lead to temperamental changes and cause madness. According to Avicenna, every human being has a special temperament and the best temperament is the one closest to moderation. The physical causes of madness can be divided into two categories: intra-brain, which causes the brain’s temperament to go out of balance, and extra-brain, which causes the temperament of other organs to go out of balance and affects the balance of the brain’s temperament. Compared to his predecessors, Avicenna talks in more detail about these temperamental factors of mental diseases and mentions other types (at least four cases) in addition to the three diseases of melancholy, phrenitis, and mania, which were called types of madness in ancient Greece, and discussed the differences between them.
Philosophical explanation (metaphysical analysis)
In general, Avicenna’s most important metaphysical basis in analyzing the issue of madness and its epistemological dimensions is the relationship between the rational soul (nafs-i nāteqah) and the body. There are three things that can be found in Avicenna’s works; if there is a problem in them, it leads to the disruption of the relationship between the rational soul and the body and provides the basis for the realization of madness. These three are as follows:
Rūh-i bukhārī: One of the important factors in the formation of this relationship is the correct and flawless functioning of the rūh-i bukhārī, which acts as a mediator between the rational soul and the body. Severe temperamental changes lead to a change in the rūh-i bukhārī and its performance, which ultimately ends in the disruption of the relationship between the rational soul and the body.
Common sense: Common sense (ḥiss al-mushtarak), as one of the internal senses is responsible for communicating between the rational soul and the five external senses, and this is the key point in analyzing the issue of madness from Avicenna’s point of view. When the rational soul has a correct relationship with the body, the five external senses perform their actions correctly, so the rational soul does not usually make mistakes in its perceptions. But, if the relationship between the intellectual faculty and the body and especially the common sense is disrupted, the rational soul is not able to match its mental form with the external world and recognize their authenticity or inauthenticity.
Imaginative faculty: If the imaginative (mukhayyalah) faculty, as one of the internal senses, is damaged or a complication occurs in it, the rational soul will not have sufficient control over it and its perceptions. At this time, the intellectual faculty will not be able to distinguish between real and unreal forms due to the lack of proper and healthy communication with the physical faculties. According to Avicenna, we have two types of imaginary forms: 1) Sometimes the perceptions resulting from the imaginative faculty are through the five external senses; 2) And sometimes there are forms that the imaginative faculty itself understands without the need for external sensory origin. When the imagination is disturbed, the rational soul will not be able to distinguish between the two types of perceptions.
Conclusion
In the physical and medical explanation, although Avicenna dealt with the issue of madness in more detail than his predecessors, such as Galen and Razi, and tried to get a more precise meaning of this phenomenon; however, its main innovation should be considered in his metaphysical analysis of madness. Avicenna’s emphasis on the examples that indicate the separation of madmen from reality leads us to the point that madness is not only a medical concept in Avicenna’s thought system; rather, it should be investigated as an epistemological and philosophical subject.