Uṣūl al-fiqh (الفقه أصول), that is, the science of Islamic jurisprudence, is deeply rooted on the notion of rational knowledge and understanding. Indeed, fiqh constitutes the body of knowledge and methods of reasoning that the Islamic jurists extract from the juridical understanding of the sources in order to provide solutions to legal problems. The point is that, according to uṣūl al-fiqh legal knowledge is achieved by rational endeavour: this is what is meant when the term ijtihād (اجتهاد ,(endeavour of the intellect; is attached to fiqh.
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