Early Islamic philosophy or classical Islamic philosophy is a period of intense philosophical development beginning in the 2nd century AH of the Islamic calendar (early 9th century CE) and lasting until the 6th century AH (late 12th century CE). The period is known as the Islamic Golden Age, and the achievements of this period had a crucial influence in the development of modern philosophy and science. For Renaissance Europe, "Muslim maritime, agricultural, and technological innovations, as well as much East Asian technology via the Muslim world, made their way to western Europe in one of the largest technology transfers in world history.” This period starts with al-Kindi in the 9th century and ends with Averroes (Ibn Rushd) at the end of 12th century. The death of Averroes effectively marks the end of a particular discipline of Islamic philosophy usually called the Peripatetic Arabic School, and philosophical activity declined significantly in Western Islamic countries, namely in Islamic Spain and North Africa, though it persisted for much longer in the Eastern countries, in particular Persia and India where several schools of philosophy continued to flourish: Avicennism, Illuminationist philosophy, Mystical philosophy, and Transcendent theosophy.
Some of the significant achievements of early Muslim philosophers included the development of a strict science of citation, the isnad or "backing"; the development of a method of open inquiry to disprove claims, the ijtihad, which could be generally applied to many types of questions (although which to apply it to is an ethical question); the willingness to both accept and challenge authority within the same process; recognition that science and philosophy are both subordinate to morality, and that moral choices should be made prior to any investigation or concern with either; the separation of theology (kalam) and law (shariah) during the early Abbasid period, a precursor to secularism; the distinction between religion and philosophy, marking the beginning of secular thought; the beginning of a peer review process; early ideas on evolution; the beginnings of the scientific method, an important contribution to the philosophy of science; the introduction of temporal modal logic and inductive logic; the beginning of social philosophy, including the formulation of theories on social cohesion and social conflict; the beginning of the philosophy of history; the development of the philosophical novel and the concepts of empiricism and tabula rasa; and distinguishing between essence and existence.
Saadia Gaon, David ben Merwan al-Mukkamas, Maimonides, and Thomas Aquinas, were influenced by the Mutazilite work, particularly Avicennism and Averroism, and the Renaissance and the use of empirical methods were inspired at least in part by Arabic translations of Greek, Jewish, Persian and Egyptian works translated into Latin during the Renaissance of the 12th century, and taken during the Reconquista in 1492.
Early Islamic philosophy can be divided into clear sets of influences, branches, schools, and fields, as described below.
In Chapter 47 of his India, entitled "On Vasudeva and the Wars of the Bharata," Abu Rayhan Biruni attempted to give a naturalistic explanation as to why the struggles described in the Mahabharata "had to take place." He explains it using natural processes that include biological ideas related to evolution, which has led several scholars to compare his ideas to Darwinism and natural selection. This is due to Biruni describing the idea of artificial selection and then applying it to nature:
In the 13th century, Nasir al-Din a In the 13th century, Nasir al-Din al-Tusi explains how the elements evolved into minerals, then plants, then animals, and then humans. Tusi then goes on to explain how hereditary variability was an important factor for biological evolution of living things:
In the 13th century, Nasir al-Din al-Tusi explains how the elements evolved into minerals, then plants, then animals, and then humans. Tusi then goes on to explain how hereditary variability was an important factor for biological evolution of living things:organisms that can gain the new features faster are more variable. As a result, they gain advantages over other creatures. [...] The bodies are changing as a result of the internal and external interactions."
Tusi discusses how organisms are able to adapt to t
Tusi discusses how organisms are able to adapt to their environments:
Tusi then explains how humans evolved from advanced animals:anthropoid apes] live in the Western Sudan and other distant corners of the world. They are close to animals by their habits, deeds and behavior. [...] The human has features that distinguish him from other creatures, but he has other features that unite him with the animal world, vegetable kingdom or even with the inanimate bodies."
Al-Dinawari (828-896), considered the founder of Arabic botany for his Book of Plants, discussed plant evolution from its birth to its death, describing the phases of plant growth and the production of flowers and fruit.
Ibn Miskawayh's al-Fawz al-Asghar and the Brethren of Purity's Encyclopedia of the Brethren of Purity (The Epistles of Ikhwan al-Safa) developed theories on evolution that possibly had an influence on Charles Darwin and his inception of Darwinism, but has at one time been criticized as overenthusiastic.