The Desirableness, Unspecified Public Interest and Fulfilling Needs.
Of the forms of inference that would lead to deducing the rules of Shari’a validly according to some Sunni Muslim scholars are Desirableness, Unspecified public interests and fulfilling needs.
The Arabic word for which are: ‘istihsan, Al-masalih Al-mursalah and sadd Al-dhara’I’
Because of the fact that none of the above forms of inference fall under the Zawahir, unequivocal meaning and indications of a text and nor under the correlative indications and relationships there is no evidence to prove them as Hujjah. In such a condition such forms of inference would fall under the category of Zann against the following of which there is clear prohibitions in the Shari’a.
Even if we would consider such forms of inference as exceptions to following non-Hujjah Zann, we will not find any other category of inference that is considered as Hujjah to include them therein.
As mentioned earlier, there is no way for reason to comprehend the basis of the rules of Shari’a independent of the instructions and explanations of the text of Shari’a and without the existence of correlative relationship indications of the texts. It also was mentioned that the case of the basis of the rules of Shari’a is similar to the case of the words of the languages the denotations of which to their meaning are not based on causative relationships.
If reason would have had the power for such discoveries then there would have been no need for the Messengers of God to come for the guidance of people and consequently every Mujtahid, scholars of the law, would become a Prophet or Imam.
The above gives lead also to the secret behind the insistence of the supporters of Ra’I that the view and opinions of a Mujtahid, through his inference is considered as always coinciding the real fact
Al-ghazali, in his works on Qiyas (al-mustasfa vol. 2. P 57) says, " There is no other evidence to prove Qiyas as Hujjah unless the Mujtahid is considered Musib, one whose views always coincide the real fact. He further says that a Mujtahid is always Musib even if his opinion would go against the text, which is unequivocal in its meaning and mistakes, are not possible for him
With a view to the above no further discussion of the above forms of inference would be need. For more readings one may find the works of Al-sayyid Muhammad Taqi Al-hakim, (An Introduction to Comparative Fiqh very useful.)
The Sources Of Authority In The Islamic Shari’a.
B. Al-‘usul Al-‘amalia, The Universal Principles for practical Applications:
The validity of the authority of the above sources of the Islamic Shari’a are all subject to strict examination by the qualified specialist of the law, the Faqih.
In the cases of the texts of the holy Quran and Sunnah the meaning must be unequivocally clear.
The decisions of reason must meet strict logical criteria.
There are considerable differences between the Shi’a and Sunni scholars as to whether all kinds of consensus is Hujjah or not. The Shi’a scholars are of the opinion that unless it is known that one of the people forming consensus is an infallible person it can not be considered as Hujjah. The discussion on Analogy or Qiyas also gives one some idea of the major differences as to what form of inference is acceptable in deducing the rules of Shari’a and which ones are not acceptable.
The biggest difference is perhaps over the narrator of Hadith.
A huge number of Ahadith in either Shi’a Muslim school of law or Sunni Muslims school of law is narrated by none Shi’a or non-Sunni Muslims. As a result of this fact there are the practical differences in both communities. On the other hand the differences over Analogy or Consensus may not have such a degree of practical differences.
In the second century when Qiyas was so popular among the scholars of some of the Sunni Muslims schools of law the Shai’a Muslims had the advantage of the presence of the Imams from the family of the holy Prophet among them. The Imams were the source for immediate answer to all of the peoples’ legal questions.
In the absence of the Twelfth Imam the Shi’a Muslim Fuqah’a also began to feel the need for working harder in rectifying the Universal Principles for Practical Utilization. Consequently, the volumes of scholarly works generated due to rectifying these universal principles has become so huge today that has grown beyond the reach of average students of the laws of Shari’a, and it has become a hard challenge for the honor students.
The expansion and elaboration of Qiyas in the second century by some of the Sunni Muslim scholars is no match, when compared, to today’s, volume, sophistication and uncompromising strict logic of the subject of the Principles of Jurisprudence, Al-‘usul Al-fiqh in the Shi’a Muslim school of law that is fast expanding. On the other hand for some mysterious reason the school of Ijtihad in the Sunni Muslim schools of law centuries ago were closed and no scholarly works on Fiqh or the ‘usul Al-fiqh is produced by any of the Sunni Muslim schools of law ever since.