This book studies the legal reasoning of Mālik ibn Anas (d. 179 H./795 C.E.) in the Muwaṭṭa' and Mudawwana. Although focusing on Mālik, the book presents a broad comparative study of legal reasoning in the first three centuries of Islam. It reexamines the role of considered opinion (ra'y), dissent, and legal ḥadīths and challenges the paradigm that Muslim jurists ultimately concurred on a "four-source" (Qurʾān, sunna, consensus, and analogy) theory of law. Instead, Mālik and Medina emphasizes that the four Sunnī schools of law (madhāhib) emerged during the formative period as distinctive, consistent, yet largely unspoken legal methodologies and persistently maintained their independence and continuity over the next millennium.