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The rulings said to depart from analogy are of two kinds: those agreed upon by consensus and those subject to disagreement. Those whose rulings are undisputed have been shown to accord with sound analogy. This gives rise to the question: may such rulings themselves serve as a basis for analogy?

A group of jurists hold that a ruling established contrary to analogy cannot serve as a basis for further analogy. This position is reported from the followers of Abū Hanīfah. The majority, however, hold that it can. This is the position stated by the followers of al-Shāfiʿī, Ahmad, and others.

They maintain that what matters is whether the conditions for analogy are met. Whenever the effective cause of a ruling is known, we extend that ruling to whatever shares the same effective cause, whether or not the original ruling is said to depart from analogy. The same applies when it is known that there is no relevant distinction between the original case and the new case. Linking cases through evidence indicating the effective cause is like linking them through the effective cause itself.

If, however, no evidence establishes that the new case is equivalent to the original case, analogy is impermissible, whether the original ruling is said to accord with analogy or to depart from it. Hence, the correct view is that the ruling on ʿarāyā sales extends to transactions equivalent to them in substance.