Ibn al-Qayyim said, “This is an eminent treatise that the scholars have unanimously accepted.”

Al-Muzanī reports that the jurists—from the time of the Companions down to his own day—were in complete agreement that whatever corresponds to truth is itself true, and whatever corresponds to falsehood is false. Accordingly, they made continual use of analogy in every field of jurisprudence.

Conditions for analogy (qiyās)
Among the essential conditions are:

1. It must not conflict with a proof stronger than itself. No weight is given to an analogy that runs counter to a Quranic text, an established consensus, or the statements of the Companions—assuming one regards a Companion’s view as authoritative. An analogy that clashes with such sources is called “invalid in consideration” (fāsid al-iʿtibār).
   Example: Someone might say that an intelligent, mature woman may contract her own marriage without a guardian by analogy with her ability to sell her own property without one. This analogy is invalid because it contradicts the explicit prophetic statement, “There is no marriage without a guardian.” (1)

2. The ruling in the original case must be established by a scriptural text or by consensus. If that ruling itself rests only on analogy, no further analogy may be built upon it. One must revert to the primary, text-based original, for the initial analogy that turned the branch into an “original” may itself be unsound, and building one analogy upon another merely prolongs the process without benefit.