Logic in Islamic philosophy#Post-Avicennian logic

Early forms of analogical reasoning, inductive reasoning and categorical syllogism were introduced in Fiqh (Islamic jurisprudence), Sharia (Islamic law) and Kalam (Islamic theology) from the 7th century with the process of Qiyas, before the Arabic translations of Aristotle's works. Later during the Islamic Golden Age, there was a logical debate among Islamic philosophers, logicians and theologians over whether the term Qiyas refers to analogical reasoning, inductive reasoning or categorical syllogism. Some Islamic scholars argued that Qiyas refers to inductive reasoning, which Ibn Hazm (994-1064) disagreed with, arguing that Qiyas does not refer to inductive reasoning, but refers to categorical syllogism in a real sense and analogical reasoning in a metaphorical sense. On the other hand, al-Ghazali (1058–1111) and Ibn Qudamah al-Maqdisi (1147-1223) argued that Qiyas refers to analogical reasoning in a real sense and categorical syllogism in a metaphorical sense. Other Islamic scholars at the time, however, argued that the term Qiyas refers to both analogical reasoning and categorical syllogism in a real sense.Wael B. Hallaq (1993), Ibn Taymiyya Against the Greek Logicians, p. 48. Oxford University Press, {{ISBN|0-19-824043-0}}.

The first original Arabic writings on logic were produced by al-Kindi (Alkindus) (805–873), who produced a summary on earlier logic up to his time. The first writings on logic with non-Aristotelian elements was produced by al-Farabi (Alfarabi) (873–950), who discussed the topics of future contingents, the number and relation of the categories, the relation between logic and grammar, and non-Aristotelian forms of inference.[http://www.britannica.com/ebc/article-65928 History of logic: Arabic logic], Encyclopædia Britannica. He is also credited for categorizing logic into two separate groups, the first being "idea" and the second being "proof".

Averroes (1126–98) was the last major logician from al-Andalus, who wrote the most elaborate commentaries on Aristotelian logic.{{Cite book|last=Fakhry|first=Majid|date=July 30, 2001|title=Averroes (Ibn Rushd) His Life, Works and Influence|url=https://books.google.com/books?id=88bWAAAAMAAJ|publisher=Oneworld Publications|access-date=September 28, 2023|isbn=978-1851682690}}

File:Avicenna.jpg

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.I. M. Bochenski (1961), "On the history of the history of logic", A history of formal logic, pp. 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]){{cite web |last1=Strobino |first1=Riccardo |title=Ibn Sina’s Logic |url=https://plato.stanford.edu/entries/ibn-sina-logic/ |publisher=The Stanford Encyclopedia of Philosophy (Fall 2018 Edition) |access-date=January 30, 2024 |date=August 15, 2018}}

The first criticisms of Aristotelian logic were written by Avicenna, 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 and the quantification of the predicates of categorical propositions, and developed an original theory on "temporal modal" syllogism. Its premises included modifiers such as "at all times", "at most times", and "at some time".

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

Ibn Hazm (994–1064) wrote the Scope of Logic, in which he stressed on the importance of sense perception as a source of knowledge.[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. Al-Ghazali (Algazel) (1058–1111) had an important influence on the use of logic in theology, making use of Avicennian logic in Kalam.

Fakhr al-Din al-Razi (b. 1149) criticised Aristotle's "first figure" and developed a form of 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 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.{{failed verification|date=September 2022}} Another systematic refutation of Greek logic was written by Ibn Taymiyyah (1263–1328), the Ar-Radd 'ala al-Mantiqiyyin (Refutation of Greek Logicians), where he argued against the usefulness, though not the validity, of the syllogismSee pp. 253–254 of {{Citation | publisher = Cambridge University Press | isbn = 978-0-521-52069-0 | pages = 247–265 |editor=Peter Adamson |editor2=Richard C. Taylor | last = Street | first = Tony | title = The Cambridge Companion to Arabic Philosophy | chapter = Logic | year = 2005}} and in favour of inductive reasoning.{{citation|first=Muhammad|last=Iqbal|author-link=Muhammad Iqbal|year=1930|title=The Reconstruction of Religious Thought in Islam|chapter=The Spirit of Muslim Culture|chapter-url=http://www.allamaiqbal.com/works/prose/english/reconstruction|access-date=2008-01-25}}

• Early Islamic philosophy
• History of logic
• Qiyas
• Ijtihad

{{reflist}}

• Rescher, Nicholas 1964. Studies in the History of Arabic Logic, Pittsburgh: University of Pittsburgh Press.
• {{cite book |last=Rescher |first=Nicholas |author-link=Nicholas Rescher |year=1966 |title=Temporal Modalities in Arabic Logic |url=https://archive.org/details/temporalmodaliti0000resc |url-access=registration |location=Dordrecht |publisher=Reidel}}

• {{IEP|av-logic|Avicenna (Ibn Sina): Logic}}
• Routledge Encyclopedia of Philosophy: [http://www.rep.routledge.com/article/H017 Logic in Islamic philosophy], Routledge, 1998
• [http://www.muslimphilosophy.com/ip/rep/H017 Logic in Islamic philosophyby Deborah L. Black] Muslimphilosophy.com:
• [https://www.historyoflogic.com/logic-islamic.htm Ancient Islamic (Arabic and Persian) Logic and Ontology], at Raul Corazzon's History of Logic.

{{Islamic philosophy |state=expanded}}

{{DEFAULTSORT:Logic In Islamic Philosophy}}

Logic

Islam