We must distinguish between faculty and function. Faculties originate functions. A faculty is a power, a potentiality. The ultimate faculty is the soul, while the ultimate function is life. There are three natural faculties: the vital (baywaniat), the natural (taby'yat), and the psychic (nafsaniat).

    There are two types of vital forces: the active and the acted upon. An active vital force would be one that causes the heart and arteries to dilate. The acted-upon vital forces are those that underlie anger, contempt, competition for victory, leadership, or fame, and other emotions. Thus, the emotional/psychological aspects of health and disease are considered holistically, as part of the entire person. For example, severe anger is believed to be the result of an excess of moisture in the heart humor, and its correction is accomplished with diet.

    There are also two types of natural forces: those that serve other functions and those that are served by others. The natural forces that are served by other forces are three kinds: the generative, the growth-promoting, and the nutritive. The servant natural forces are four: the attractive, the retentive, the digestive, and the propulsive. These various forces interact intimately each with the other. The four servant forces serve the nutritive forces (by attracting, retaining, digesting, and propelling), and the nutritive force serves the growth-promoting force. The tint two forces serve the generative force.

    The psychic forces perform three functions: (1) to mediate behavior, (2) to cause voluntary movement, and (3) to create sensation. Within these functions are found the various events that serve imagination, create thinking, and underlie memory.

    Astronomy was widely regarded as an integral part of medical science. The stars were seen as directly influencing the condition and well-being of human beings on earth. Many hakims believed in the importance of the position of the planets in treating their patients. It was believed that the position within the zodiac at any time of seven planets--Saturn, Jupiter, Mars, Venus, Mercury, Sun and Moon--affected human beings. The survival of a baby born before the normal period of gestation was completed, for instance, was believed to depend to some extent on the planet in ascendancy at the time of its birth.

    The twelve signs of the zodiac were divided into three groups: the four elements (fire, earth, air and water); the four humours (blood, phlegm, black bile and yellow bile); and the four qualities of temperature and humidity (cold, hot, moist and dry).19

    This cosmic make-up clearly conformed to, and reflected, the principal concepts of Unani medicine.

    The correction of subtle emotional and spiritual imbalances, while of concern to the Hakim, is often treated by spiritual remedies and practices. See The Book of Sufi Healing which elaborates the spiritual side of Unani healing.

    Thus, according to the Unani system, all of the physical, emotional, and spiritual mechanisms of life are included in the evaluation of a person's health. I mentioned before that according to Tibb, the human being possesses a soul (rub), which is independent of and superior to all of the physiological functions of the body--including all mental functions, such as thought processes, memory, and the emotions. Once a human life ends, the activization of the three faculties ends, all physical functions cease, and we observe what is called death.

    The science of maintaining the human body in a state of balance, harmony, and vigor is the purpose of Unani--the treatment of the physical, mental, and spiritual forces of human life. The foregoing is a necessary explanation of the basic theories of the human being and its parts.