والعمدة فيها طريقان
The principal reliance is on two methods.
The first is dawarān, named in the text as the term of later scholars, linked with the earlier expression ṭard wa-ʿaks. The second is sabr wa-taqsīm, examining possible attributes and excluding those unfit to explain the ruling.
Both seek more than surface resemblance: they investigate which feature actually grounds the judgment.