A Reality Check on Istihsan as a Method of Islamic Legal Reasoning

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UCLA Journal of Islamic and Near Eastern Law


At one time, certain Western scholars of Islamic law mistakenly viewed the concept of istihsan as a form of equity. This error was noted in my earlier study of istihsan, and I redefined the concept as an application of legal logic by referring back to classical works on jurisprudence authored by Islamic jurists.' These classical works defined istihsan as either (1) the preference for a recognized source of law over reasoning by analogy (qiyas), or (2) the preference for one reasoning by analogy over another that is considered weaker. Istihsan is a method by which new rules of Islamic law are derived through what might be called the reasoned distinction of authority. This earlier study, however, confined itself to works on jurisprudence, otherwise known as usul al-fiqh or "the roots of the law." Such works seek to describe the manner in which legal reasoning operates in Islamic law, and throughout their pages one finds debates over the legitimacy of different sources of law and methods of legal reasoning. Since jurisprudence is a field where political, theological and philosophical points of view are advocated, the usulis (authors of these jurisprudential works) could be suspected of distorting their descriptions of the practice of law to favor one theory of jurisprudence over another. This very issue was raised at a conference a few years ago when several specialists on the works of usul al-fiqh raised a question about the objectivity of these works.3 Did these works describe the real state of legal reasoning in the actual practice of law in Islam? For the concept of istihsan, the question specifically is whether the jurisprudential concept of istihsan, described by the usulis as the reasoned distinction of authority, is the same as the practical concept of istihsan used by jurists in the solution of actual legal cases. To answer this question one must examine the original sources that expound the law as it is developed, not that describe it as part of an author's theory. In American law, these original sources are found in statutes and cases. In Islamic law too, these original sources are found in statutes and cases. As will be explained more fully in the section of this article on statutory interpretation, statutes in Islamic law are the Qur'an and sunna of the Prophet. Cases are the myriad of legal opinions issued by jurists throughout the centuries of Islamic law. During its first millennium, Islamic law witnessed the grand development of its legal system through a coordinate organization of scholars and judges. There was no dependence on popular legislation or hierarchical bureaucracy. Rather, the development of law occuffed through legal opinions that solved problems on the basis of concrete facts in particular cases. In this regard, Islamic law was very similar to the development of the common law in England before the 19th century. Legal opinions (fatwas) in Islam are documented in a variety of treatises, which fall under the category of fiqh, the term for "law" in Islam. They can be found gathered in the form of collections, or they may be organized and analyzed in the form of abridgements (mukhtasars), treatises, commentaries (sharhs), and supercommentaries (hashiyas). These forms of legal literature are similar to the collections of cases in the common law system that occupy rows of bookshelves in American law libraries, and to the treatises that organize and analyze these cases in the form of nutshells, casebooks and hombooks. This article focuses on one of these works of fiqh to explore the use of istihsan as a methodological device in Islamic legal opinions, specifically in the area of sales. The fiqh work is a well-known treatise in the Hanafi school of law entitled Bada'i' al-Sana'i' fi Tartib al-Shara'i', written by 'Ala' al-Din Abu Bakr ibn Mas'ud al-Kasani (d. 587/1 191). The 1971 Cairene edition is a ten-volume work covering several areas of law in 5,000 pages, and the area of law on sales is covered in a little over 400 pages in a chapter entitled Kitab al-Buyu' ("Book of Sales"). In this chapter we find 37 cases that refer explicitly to the use of istihsan as a methodological device used to derive solutions of law. This article will analyze the first fourteen cases of istihsan in Kasani's Book of Sales to determine whether its use in each of the cases matches the definition of istihsan as it is propounded in the works on usul alfiqh. Contrary to works on usul al-fiqh, Kasani's Book of Sales does not seek to explain the different methodologies for deriving rules of law, but rather it reports legal opinions that derive rules to decide cases. The legal opinions describe the process by which the rules are derived and, in so doing, use methodological devices such as istihsan to reach their conclusions. There is no analysis, however, of the methodological devices themselves, such as is found in the usul works. This study will compare what the usulis had to say about istihsan with what is found by way of the actual use of istihsan in the fourteen legal cases that use istihsan to solve problems in the area of sales. Let us recall in more detail what the usulis had to say about istihsan. Bazdawi and Sarakhsi in the Hanafi school of law clearly defined istihsan as one of several techniques for preferring a solution of law over the one prescribed by reasoning by analogy (qiyas). One method is to find a reasoning by analogy that is stronger, and this method may be called the reasoned distinction of reasoning by analogy. Another method is the abandonment of reasoning by analogy in favor of a tradition (athar) in the Qur'an or the sunna, or in favor of consensus (ijma'), or in favor of necessity. Together, these two methods of legal reasoning may be called the reasoned distinction of authority. The first method that distinguishes between two reasonings by analogy distinguishes a case that has been justified by a certain cause ('illa) from a new case that appears to be governed by the same cause. If two cases are governed by the same cause, they both must follow the rule (hukm) of the case. In order to distinguish the first case from the second so that the two cases are governed by two different rules, the cause in the first case is reexamined and a different cause is found - one that exists only in the first case but not in the second. Thus, the rule that governs the first case now no longer governs the second. The reasoning by which the original cause is abandoned in favor of a new cause is considered stronger than the reasoning that produced the original cause, and it is called istihsan. The new cause permits the outcome in the first case to remain the same, but allows a different outcome in the second case. A classic case described in the literature is the case that forbids the eating of food left by predatory animals. The cause of the prohibition was originally conceived to be the uncleanliness of the meat of the predatory animal that made the food they touched unclean. Therefore, the food left by predatory birds would be unclean because their meat was unclean. Jurists reasoned, however, that a better reason for the prohibition on food left by predatory animals is the fact that saliva from the meat of the predatory animal is mixed with the food they touch and this mixing makes the food impure. On the other hand, since the skin, bone and hair of predatory animals is clean, and since the beak of a bird does not emit saliva, the food touched by predatory birds is clean. Thus, the original prohibition on the eating of food touched by predatory birds is changed to a permission by defining the cause of the prohibition through a better (istihsan means, literally, the deeming of something good (hasan)) reasoning process than originally took place. The second method of abandoning reasoning by analogy is to favor a recognized source of law, such as the Qur'an, sunna, consensus or necessity, over reasoning by analogy. This second method is described in the usul works as the creation of specific exceptions to general rules derived by reasoning by analogy. For example, qiyas requires that the object of a contract be present at the time of the making of the contract, but a tradition from the sunna permits a salam contract (the regulated sale of an object to be delivered in the future) as an exception to this general rule.

In sum, the usuli definition of istihsan is that it is a methodological device to derive a new rule to govern a case that appears to fall under an old rule, and we call this device the reasoned distinction of authority. The question to be answered is whether the first fourteen cases of istihsan that are specifically referenced by Kasani in his Book of Sales will confirm this definition. As we explore these cases in the following pages, I have taken the liberty of giving names to the Islamic cases in order to distinguish them as cases and to provide a means of easy reference. Furthermore, as an aid to understanding, these cases are compared with American cases that use a similar process of legal reasoning.' 5 The comparison should provide a shortcut to discerning the true significance of istihsan by identifying familiar ground. In all these cases we find that the practical concept of istihsan and its American counterpart matches the jurisprudential concept described by the usulis. It confirms the usuli definition of istihsan. What is interesting about the practical use of the concept as seen in these fourteen cases, however, is that it reveals a legal reasoning process that is not fully appreciated if one reads the usul works alone.

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