The intended meaning of consensus is the agreement of all Muslims or all scholars on a religious ruling, which proves the religious ruling for those who believe in its authority; because it is impossible for all Muslims or all scholars to agree on falsehood. This is true considering the presence of Allah’s caliph among them; as Allah Almighty has said: ﴿وَمِمَّنْ خَلَقْنَا أُمَّةٌ يَهْدُونَ بِالْحَقِّ وَبِهِ يَعْدِلُونَ﴾[1]; “And among those We have created, there are some who guide with the truth and establish justice with it,” and therefore, it is religiously impossible for them to agree on falsehood. However, this agreement is neither known nor beneficial; because it is impossible to count the opinions of all Muslims or all scholars due to their vast number and the fact that some are hidden. Moreover, what they all consider proven does not need to be proved, so there is no need to use their agreement as evidence to prove it! It is understood from here that the impossibility of proving an Islamic ruling based on consensus is a case of negation due to the non-existence of the subject; considering that complete induction is impossible on the one hand, and achieving what is already achieved is impossible on the other hand. This is what His Eminence Mansoor means by the lack of authority of consensus.

As for “the consensus of a group of experts,” it is a contradictory phrase; because its concept implies the existence of disagreement among the experts, and it is self-evident that their disagreement is not the same as their agreement. Consensus is only the agreement of all, which is impossible to achieve, whether in religious matters or natural sciences. Yes, it is possible to know the opinions of many of them and not know any dissenting opinions, and this is what some call consensus out of leniency. However, the intellect does not consider it sufficient to prove any ruling, even if it is a natural one; just as “a group of experts” agreed for hundreds of years that the Earth was flat, that the sun revolved around it, and that there were four elements, nine celestial spheres, and seven regions in the world, without any known dissenters to them, and yet it turned out to be incorrect.

As for referring to Allah’s caliph in sciences with a non-religious nature, such as physics, engineering, agriculture, management, economics, and medicine, it is not obligatory; because these sciences have a real, non-nominal nature and are known through the intellect, except in aspects of them that have religious rulings, such as rulings on building a house high and building a toilet facing the Qiblah, rulings on farming, musaqat, and mudarabah, rulings on usury and forbidden businesses, the ruling on the doctor’s liability, and so on. Despite this, referring to Allah’s caliph in these sciences can also be extremely beneficial. Rather, it is not unlikely that many of these sciences were taught by Allah’s caliph; as it has been narrated that Adam was the first to recite poetry, and Idris was the first to write with a pen, and he was the first to sew and wear clothes, and people before him wore animal skins, and it has been said that Allah taught him about the stars, arithmetic, and astronomy, and it has been narrated that Nuh was the first to build a ship that sailed on water, and the first to arrange an army in war with a right flank, left flank, and center and to raise banners was Ibrahim when he marched to fight those who had captured Lut and he was the first to wear sandals, and the first to ride a horse was Isma‘il and horses were previously wild and untamed, and the first to create measures and scales was Shu‘aib and the first to make armor was Dawud ; it was previously made of solid plates, then he wove it into a chainmail design so that it would be lighter and sturdier, and the words of Allah Almighty indicate this, where He has said: ﴿وَعَلَّمْنَاهُ صَنْعَةَ لَبُوسٍ لَكُمْ لِتُحْصِنَكُمْ مِنْ بَأْسِكُمْ ۖ فَهَلْ أَنْتُمْ شَاكِرُونَ﴾[2]; “And We taught him the making of armor for you, to protect you from your violence. Will you then be grateful?” and the first to make sugar was Sulayman and he was the first for whom a mixture of lime and arsenic was made and who entered the bathhouse, and the first to build a dam on Earth was Dhul-Qarnayn, and Allah knows best.