Following notes on Istihsan have been taken from Principles of Mahomedan law By D.F Mulla.
The doctrine by which a jurist is enabled to get over a deduction of analogy, either because it is opposed to a text or consensus of opinion, or is such that his better judgement does not approve of it, is technically called Istihsan.
Istihsan literally, preferring or considering a thing to be good) which I have translated juristic preference or equity.
The term Istihsan is used by the Hanafi lawyers alone, and so much of the doctrine itself which authorizes a jurist to rely on his private judgement, instead of following a rule resting on analogy, is also confined to the Hanafi system.
It has largely helped to develop the Hanafi system, the founder of which deserves the credit of having been the first to recognize that a strict adherence to analogy would deprive law of that elasticity and adaptability which alone make it the handmaid of justice.
The principle of Istihsan evoked strong comments and opposition from jurists of the other Sunni Schools, and Shafi’i is reported to have said : ‘ whoever resorts to Istihsan makes laws.’
Different kinds of juristic equity as opposed to kinds of analogical deduction
Laws based on juristic equity are divided by some lawyers into two classes : (a) those that carry conviction to the mind of a jurist as being sound, and (b) those that appear at the first glance to be sound, but do not produce such conviction in the mind of different the jurist. In juxtaposition to this classification of juristic equity law, analogical deductions are similarly classified into (1) those that are weak and (2) those which at the first glance appear to be unsound, but are found on further examination to be correct. When opposed to each other (a) is to be preferred to (1) and (2) to (b).
Application of Juristic equity:
The doctrine is chiefly resorted to, in cases arising out of the complex conditions of a growing society where a strict adherence to analogy would fail to meet the wants of the people.
It will also be remembered that it is on the strength of this principle that the Hanafi doctors abandon a rule of analogy in favour of a different rule sanctioned by custom as being more acceptable to the people.
Public Doctrine of Public Good
Imam Malik sanctioned a doctrine somewhat similar to juristic equity or preference. He would allow a deduction of law to be based on general considerations of the public good (masalihu’l-mursala wa’1-istislah) and Imamu’l-Haramain also held a similar view.
Ijtihad and Taqlid
Is further juristic exposition and development of the Muhammadan Law precluded
With reference to the sources of law, it is a matter of considerable importance that we should consider the question whether further juristic exposition and development of the Muhammadan law is inconsistent with the principles of the system.
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