Avicenna Avicenna

Influence in philosophy and science

In 1919–20 British Orientalist and acclaimed authority on Persia Edward G. Browne opined that “Avicenna was a better philosopher than physician, but al-Rāzī [Rhazes] a better physician than philosopher,” a conclusion oft repeated ever since. But a judgment issued 800 years later begs the question: By what contemporary measure is an appraisal of “better” made? Several points are needed to make the philosophical and scientific views of these men comprehensible today. Theirs was the culture of the ʿAbbāsid Caliphate (750–1258), the final ruling dynasty built on the precepts of the first Muslim community (ummah) in the Islamic world. Thus, their cultural beliefs were remote from those of the 20th-century West and those of their Hellenistic predecessors. Their worldview was theocentric (centred on God)—rather than anthropocentric (centred on humans), a perspective known to the Greco-Roman world. Their cosmology was a unity of natural, supernatural, and preternatural realms.
Avicenna’s cosmology centralized God as the Creator—the First Cause, the necessary Being from whom emanated the 10 intelligences and whose immutable essence and existence reigned over those intelligences. The First Intelligence descended on down to the Active Intelligence, which communicated to humans through its divine light, a symbolic attribute deriving authority from the Qurʾān.
Avicenna’s most important work of philosophy and science is Kitāb al-shifāʾ, which is a four-part encyclopaedia covering logic, physics, mathematics, and metaphysics. Since science was equated with wisdom, Avicenna attempted a broad unified classification of knowledge. For example, in the physics section, nature is discussed in the context of eight principal sciences, including the sciences of general principles, of celestial and terrestrial bodies, and of primary elements, as well as meteorology, mineralogy, botany, zoology, and psychology (science of the soul). The subordinate sciences, in order of importance, as designated by Avicenna, are medicine; astrology; physiognomy, the study of the correspondence of psychological characteristics to physical structure; oneiromancy, the art of dream interpretation; talismans, objects with magical power to blend the celestial forces with the forces of particular worldly bodies, giving rise to extraordinary action on earth; theurgy, the “secrets of prodigies,” whereby the combining of terrestrial forces are made to produce remarkable actions and effects; and alchemy, an arcane art studied by Avicenna, although he ultimately rejected its transmutationism (the notion that base metals, such as copper and lead, could be transformed into precious metals, such as gold and silver). Mathematics is divided into four principal sciences: numbers and arithmetic, geometry and geography, astronomy, and music.
Logic was viewed by Avicenna as instrumental to philosophy, an art and a science to be concerned with second-order concepts. While he was generally within the tradition of al-Fārābī and al-Kindī, he more clearly dissociated himself from the Peripatetic school of Baghdad and utilized concepts of the Platonic and Stoic doctrines more openly and with a more independent mind. More importantly, his theology—the First Cause and the 10 intelligences—allowed his philosophy, with its devotion to God as Creator and the celestial hierarchy, to be imported easily into medieval European Scholastic thought.