Aql () is an Arabic term used in Islamic philosophy and theology for the intellect or the rational faculty of the soul that connects humans to God. According to Islamic beliefs, aql is what guides humans towards the right path (sirat al-mustaqim) and prevents them from deviating. In jurisprudence, it is associated with using reason as a source for sharia and has been translated as 'dialectical reasoning'.
The term "al-'aql" in Arabic is derived from the root word "ql," which means to bind. In Islamic thought, it is used to describe the faculty that connects individuals to God. It is usually translated in English as intellect, intelligence, reason or rational faculty.
The Quran doesn't use the word "aql" explicitly, but its verbal forms such as yaÿqelà «n appear 49 times. Intellect is important because it allows humans to understand God's signs in nature (2:164, 13:4, 16:12, 23:80) and in the Quran or other scriptures (2:44, 3:65, 3:118, 10:16, 11:51). Intellect prevents humans from committing actions that would lead them to punishment in hell (67:10). Moreover, it allows individuals to comprehend that the afterlife is better than this world (6:32, 7:161, 12:109, 28:60). Those who lack intellect are seen as the worst creatures in God's sight ("Surely the worst of beasts in God's eyes are those who are deaf and dumb and do not use their intellect") (8:22). Elsewhere, the Quran says: "Have they not traveled in the earth that they might have hearts with which to intellect and ears with which to hear? Surely the eyes are not blind, but blind are the hearts within the breasts". (22:46).
Moreover, the term à «luâÂÂl-albÃÂb (possessors of intellect) is mentioned 16 times in the Quran, and commentators often associate their "lobb" with intellect. The Quran (39:9) poses a rhetorical question, asking whether those who possess knowledge and those who do not are equal. The answer, according to the Quran, is that only the à «luâÂÂl-albÃÂb (the possessors of intellects) are the ones who remember and understand the significance of God's signs.
While Sunni Hadiths acknowledge the value of intellect, Shia Hadith collections contain a larger number of traditions that praise it. The connection between intellect and sound religious faith and practice is emphasized in both Sunni and Shia traditions. According to ḠazzÃÂlë, the Prophet said that intellect is the foundation of the believer, and it determines the extent of their worship. The Shiÿite sources, in particular, stress the idea that intellect is the foundation of all positive moral qualities. In that vein, Imam Jaÿfar al-á¹¢ÃÂdeq defines intellect as the means by which one worships the All-Merciful and attains Paradise.
The term âÂÂaql was heavily elucidated by early ShëâÂÂah thinkers; it came to replace and expand the pre-Islamic concept of ḥilm () "serene justice and self-control, dignity" in opposition to the negative notions of ignorance (jahl) and stupidity (safah).
The "possessor of âÂÂaql", or al-âÂÂÃÂqël (plural al-âÂÂuqqÃÂl) realises a deep connection with God. Jaÿfar aá¹£-á¹¢ÃÂdiq (d. 765, notably an ImÃÂm) described this connection as a realisation that God loves some, that God is truth and that only âÂÂilm "sacred knowledge" and its development can help humanity fulfil its potential.
His son, ImÃÂm Mà «sàal-KÃÂà ¼im (d. 799), expanded this exegesis by defining âÂÂaql as the "faculty for apprehending the divine, a faculty of metaphysical perception, a light in the heart, through which one can discern and recognize signs from God." He further noted that where the A'immah (ImÃÂms) are the ḥujjatu à ¼-à ¼ÃÂhira "External proof [of God]", âÂÂaql is the ḥujjatu l-BÃÂá¹Âina "Secret proof".
While in early Islam, âÂÂaql was opposed to jahl "ignorance", the expansion of the concept meant it was now opposed to safah "[deliberate] stupidity" and junà «n "lack of sense, indulgence". Under the influence of MuâÂÂtazilë thought, âÂÂaql came to mean "dialectical reasoning".
In ShëâÂÂë jurisprudence, âÂÂaql is the process of using intellect or logic to deduce law. Legal scholars in both Sunni and ShëâÂÂë Islamic traditions share Quranic interpretation, the Sunnah, and Ijmaâ "consensus" as sources of Islamic law and judicial decisions (ḥukm). However, Twelvers of the JaâÂÂfarë school of law utilize âÂÂaql whereas Sunnis use qiyas "analogical reasoning" as the fourth source of law.
Among Twelvers, AkhbÃÂrës (associated with exotericism and traditionalism and theological schools in Qom) and Usulis (associated with esotericism and rationalism and theological schools in Baghdad) were contending subschools: the former reject ijtihÃÂd outright; the latter advocate ijtihad and have been predominant for the last 300 years.
In ShëâÂÂë Islam, "the gates of ijtihÃÂd" were never closed and with the use of âÂÂaql, ShëâÂÂë mujtahids "practitioner of ijtihÃÂd" and faqëhs "legal specialists" are able to respond as issues arise that were not explicitly dealt with in the Qur'an or Sunnah.