Editing Early Islamic philosophy (section)

===Avicennian logic===
[[Avicenna]] (980–1037) developed his own system of logic known as "Avicennian logic" as an alternative to Aristotelian logic. By the 12th century, Avicennian logic had replaced Aristotelian logic as the dominant system of logic in the Islamic world.<ref>I. M. Bochenski (1961), "On the history of the history of logic", ''A history of formal logic'', p. 4-10. Translated by I. Thomas, Notre Dame, [[Indiana University Press]]. ([[cf.]] [http://www.formalontology.it/islamic-philosophy.htm Ancient Islamic (Arabic and Persian) Logic and Ontology] {{Webarchive|url=https://web.archive.org/web/20071030161609/http://www.formalontology.it/islamic-philosophy.htm |date=2007-10-30 }})</ref>

The first criticisms of Aristotelian logic were written by [[Avicenna]] (980–1037), who produced independent treatises on logic rather than commentaries. He criticized the logical school of Baghdad for their devotion to Aristotle at the time. He investigated the theory of [[definition]] and [[Classification theorems|classification]] and the [[Quantification (logic)|quantification]] of the [[predicate (mathematical logic)|predicate]]s of categorical [[Proposition (philosophy)|proposition]]s, and developed an original theory on "[[Temporal logic|temporal]] [[Modal logic|modal]]" syllogism. Its premises included [[Grammatical modifier|modifier]]s such as "at all times", "at most times", and "at some time".

While [[Avicenna]] (980–1037) often relied on [[deductive reasoning]] in philosophy, he used a different approach in medicine. Ibn Sina contributed inventively to the development of [[inductive reasoning|inductive logic]], which he used to pioneer the idea of a [[syndrome]]. In his medical writings, Avicenna was the first to describe the [[Mill's Methods|methods of agreement, difference and concomitant variation]] which are critical to inductive logic and the [[scientific method]].<ref name=Goodman>Lenn Evan Goodman (2003), ''Islamic Humanism'', p. 155, Oxford University Press, {{ISBN|0-19-513580-6}}.</ref>

[[Ibn Hazm]] (994–1064) wrote the ''Scope of Logic'', in which he stressed on the importance of [[sense]] [[perception]] as a source of knowledge.<ref name=Herald>[http://www.islamherald.com/asp/explore/science/science_muslim_scientists.asp Science and Muslim Scientists] {{Webarchive|url=https://web.archive.org/web/20071020090525/http://www.islamherald.com/asp/explore/science/science_muslim_scientists.asp |date=2007-10-20 }}, Islam Herald.</ref> [[Al-Ghazali]] (Algazel) (1058–1111) had an important influence on the use of logic in theology, making use of Avicennian logic in [[Kalam]].<ref name=Britannica/> Despite the logical sophistication of [[al-Ghazali]], the rise of the [[Ash'ari]] school in the 12th century slowly suffocated original work on logic in much of the Islamic world, though logic continued to be studied in some Islamic regions such as [[History of Iran|Persia]] and the [[Levant]].

[[Fakhr al-Din al-Razi]] (b. 1149) criticised Aristotle's "[[Syllogism|first figure]]" and developed a form of [[Inductive reasoning|inductive logic]], foreshadowing the system of inductive logic developed by [[John Stuart Mill]] (1806–1873). Systematic refutations of Greek logic were written by the [[Illuminationist philosophy|Illuminationist school]], founded by [[Shahab al-Din Suhrawardi]] (1155–1191), who developed the idea of "decisive necessity", an important innovation in the history of logical philosophical speculation.<ref name=Herald/> Another systematic refutation of Greek logic was written by [[Ibn Taymiyyah]] (1263&ndash;1328), the ''Ar-Radd 'ala al-Mantiqiyyin'' (''Refutation of Greek Logicians''), where he argued against the usefulness, though not the validity, of the [[syllogism]]<ref>See pp.&nbsp;253&ndash;254 of {{Citation | publisher = Cambridge University Press | isbn = 978-0-521-52069-0 | pages = 247&ndash;265 |editor= Peter Adamson |editor2=Richard C. Taylor | last = Street | first = Tony | title = The Cambridge Companion to Arabic Philosophy | chapter = Logic | year = 2005}}</ref> and in favour of [[inductive reasoning]].<ref name=Iqbal/>