Qiyas is an analogical deduction from the above three sources of law. It is use of Human reasoning to compare on existing situtation with one for which the legislation already exists. If a problem arises, which none of these have dealt directly then the scholars try to find a law in any of them, which has a similar cause, and classify the problem in the same manner. Imam Abu Hanifa was the first to adopt this method for formulating law.
The Holy Quran has recognized the exercise of private judgement. The Quran says, “They have hearts wherewith they understand not eyes wherewith they see not and ears wherewith they hear not. The are as cattle nay more misguided for they are heedles (of warning)”.
Again it says: “Take warning then, O you with eyes (to see).” (59:2)!
Allah says, :There are signs in this for people who understand”.
The Prophet (S.A.W) is reported to have encouraged it in his lifetime. He asked Muad when he was deputed to Yemen as a governor, “How will you decide when a matter comes to you for decision?” He replied, “I shall decide according to book of Allah”. Prophet (S.A.W) said, “If you do not find it in the book of Allah? Muad said, “Then according to the Sunnah of the Prophet.” He asked, “If you find nothing therein”. “Then I will exert myself to form my own judgement”.Muad replied. (Tirmidhi and Abu Daud).
According to another tradition the Prophet (S.A.W) is reported to have told Abu Musa Al-Ashari, “Judge upon the Book of Allah, If you do not find in it what you need, upon the Sunnah of the Prophet (S.A.W), and if you do not find in that, also, then use you personal opinion”. (Tirmidhi, Abu Daud).
Argument on Qiyas
The opponents of Qiyas argue that to consider Qiyas as an additional evidence would be t9o consider the Quran insufficient, since the Quran says “We have sent down to you the book as an explanation for every thing”. (16:91).
They also argued on the basis of a tradition of the Prophet (S.A.W) said, “The affairs of the sons of Israel have continued to prosper until there multiplied among them the children of the war captives, for these have measured (qasu) what did not exist on the basis of what did exist, and they have erred and led others into error.”
But the supporters argue that all the companion of the Prophet (S.A.W) and the followers have used Qiyas as a source of law and they quote the verse of Quran in their support, “Take warning then O you with eyes (to see).”. (59:2).
It is also argued that there is doubt about the “effective cause” for which shariah value has been established because the revealed text does not mention the causes and consequently one does not know what to use as a basis for Qiyas, furthermore, God is not worshipped according to the dictate of reasosn.
Components of Qiyas
v The fundamental teaching on which Qiyas is based (asl, root)
v The subsidiary, the new condition in question (fare:branch)
v The cause that connects both the cases (ilia)
v The law that is extended to the new case (Hukm)
v This may be illustrated by the following example
v The fundamental teaching. The Prophet (S.A.W) said “Every intoxicant is Khamr so every intoxicant is haram”.
v Far’e the (subsidiary) :L.S.D cocaine opium and all other drugs
v Ilia (the cause) connecting them: intoxication
v Hukam (Law): all these drugs are declared haram (forbideen)
The conditions of Qiyas
v That the value such as prohibition which is to be extended to a new situation should not be expressly limited to the original case.
v That the value of the original case should not have been against the rule of analogy.
v The value whose extension to a new shariah value is sought should be shariah established by the Quran sunnah or Ijma but not another Qiyas.
v The application of qiyas should not result in the altering of the prescription because it would be altering the divine precription on the basis of perosnal judgment.
Examples of Law Derived by Qiyas
Drugs like marijuana, LSD, cocaine and opium were not found during the time of the Prophet (S.A.W) so nothing directly was said about them. However, the Prophet (S.A.W) had said, Every intoxicant is Khamr, so every intoxicant is Haram”.
Since these drugs are highly intoxicating, they are all declared haram. Another example is that Wudu is not valid even if the smallest portion of the body, which has to be washed remains dry. According to a tradition reported by Aisha (R.A) if flour is dried on the nails and water has not reached any portion of that nail, Wudu would not be considered to have taken place, so applying this in the case of nail polish, the Wudu is not conisdered to have taken place as the nails remain dry.
Thus Istihsan is an efficient method of legal reasoning that ensures analytical consistency in the system and helps the Jurists identify general principles and exception besides giving important to the consequence (result) of the decision.