Bu makalenin amacı, Hanefilerin illet konusundaki görüşlerini tümevarım metodu ile inceleyiponların te’sir teorisini ortaya çıkarmaktır. Bu çalışmada sadece Hanefilerin usûl eserleri dikkatealınmıştır. Makelemiz iki bölümden oluşmaktadır. Birinci bölümde bir sonraki bölümde ele alınacakte›sir konusuna zemen teşkil eden illet tanımları kısaca tahlil edilmiştir. Mekalenin esasınıteşkil eden ikinci bölümde ise te›sir toerisinin Iraklı Hanefilerin ellinde ortaya çıkışına daha sonraBuhara›daki Hanefilerin buna katkılarına ve son olarak te›sir toersinin müteahhirîn dönemi Hanefileritarafından geliştirilmesine temas edilmiştir.Anahtar kelimeler: Usûlu’l-Fıkıh, kıyas, İllet, te’sir, alâmet, mulâemet.Theory of effectiveness (ta’thir) of causality (illa) in the legal theory of Hanafi school.Abstract: This research aims to elaborate the theory of effectiveness (ta’thir) of causality (illa)in the Hanafi school. This is carried out through the induction of different opinions from Hanafischolars in the subject of effectiveness (ta’thir) of causality (illa). The study confines to Usûl al-fiqhliterature of Hanafi school. The research consists of two sections. The first section deals with theviews of Hanafi scholars regarding causality (illa) as well as their definitions in a summarized form.The importance of this section is reflected through the role it plays, of forming the ground basis forthe theory of effectiveness (ta’thir) in the second section. The second section forms the core ofresearch. It focuses on the phases of evolution of effectiveness (ta’thir) theory in Hanafi school.It discusses genesis, development, and culmination of the concept of effectiveness (ta’thir) theorythrough out Hanafi legal theory.Key words: Legal theory (Usûl al-fiqh), analogy (qiyas), causality (illa), effectiveness (ta’thir), sign(alâma), conformity (mulâ’ama).

This research aims to elaborate the theory of effectiveness (ta’thir) of causality (illa) in the Hanafi school. This is carried out through the induction of different opinions from Hanafi scholars in the subject of effectiveness (ta’thir) of causality (illa). The study confines to Usûl al-fiqh literature of Hanafi school. The research consists of two sections. The first section deals with the views of Hanafi scholars regarding causality (illa) as well as their definitions in a summarized form. The importance of this section is reflected through the role it plays, of forming the ground basis for the theory of effectiveness (ta’thir) in the second section. The second section forms the core of research. It focuses on the phases of evolution of effectiveness (ta’thir) theory in Hanafi school. It discusses genesis, development, and culmination of the concept of effectiveness (ta’thir) theory through out Hanafi legal theory.