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The Economy of Certainty

By Aron Zysow


Aron Zysow's 1984 PhD dissertation, "The Economy of Certainty," remains the most important, compelling, and intellectually ambitious treatment of Islamic legal theory (usul al-fiqh) in Western scholarship to date. It continues to be widely read and cited, and remains unsurpassed in its incisive analysis of the most fundamental assumptions of Islamic legal thought.

Zysow argues that the great dividing line in Islamic legal thought is between those legal theories that require certainty in every detail of the law and those that will admit probability. The latter were historically dominant and include the leading legal schools that have survived to our own day. Zahirism and, for much of its history, Twelver Shi'ism, are examples of the former. The well-known dispute regarding the legitimacy of juridical analogy is only one feature of this fundamental epistemological division, since probability can enter the law in the process of authenticating prophetic traditions and in the interpretation of the revealed texts, as well as through analogy. The notion of consensus in Islamic legal theory functioned to reintroduce some measure of certainty into the law by identifying one of the competing probable solutions as correct. Consequently consensus has only a reduced role, if any, in those systems that reject probability. Another, more radical, means of regaining certainty was the doctrine that regarded the legal reasoning of all qualified jurists on matters of probability as infallible. The development of legal theories of both types, that of Zahirism no less than that of Hanafism, was to a large extent shaped by theology and, most significantly, by Mu'tazilism, and subsequently by Ash'arism and Maturidism.

Zysow's important work is published here in full, for the first time, with updated references and some further reflections by the author.

The Economy of Certainty

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    RAIS vol. 2

    360 pages
    10 x 7 inches

    978-1-937040-09-3 (paperback)

    978-1-937040-27-7 (PDF)

    July 2013

  • Table of Contents

    Series Editors’ Preface


    Author’s Preface






    1 The Authentication of Prophetic Traditions

    I The Concurrent Tradition

    II The Mashhur Tradition

    III The Unit-Tradition

    IV Discontinuity




    2 Interpretation

    I The Nature of Islamic Hermeneutics

    II The Hermeneutical Apparatus

    III The Linguistic Postulates

    IV The Imperative

    V The General and Special Terms

    VI Zahiri Hermeneutics

    VII The Argumentum a Fortiori

    VIII The Argumentum a Contrario




    3 Consensus

    I Introduction

    II The Basis of the Doctrine of Consensus

    III The Operation of Consensus

    IV Tacit Consensus

    V Consensus of the Majority

    VI Inqirad al-’asr

    VII Consensus after Disagreement

    VIII Zahirism and the Support of Consensus

    IX Conclusion




    4 Analogy

    I Introduction

    II The Foundations of Analogy

    III Noncausal Analogy

    IV The Epistemology of the Cause

    V The Ontology of the Cause

    VI Al-Masalih al-mursala

    VII Istihsan

    VIII Specialization of the Cause




    5 Ijtihad

    I Ijtihad and Probability

    II Infallibilism

    III Consequences of Infallibilism





    I The Supposed Zahirism of Ibn Tumart and Ibn ‘Arabi

    II Twelver Shi’ism

    III Conclusion




    Works cited in the Addenda and Preface

    Table of Page Correspondences

    Index of Qur’an Citations

    Index of Arabic Terms and Proper Names


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