al-Shafi‘i said: It is not taken in exchange for it, according to one of the two views, because paralysis is an ailment, and the effects of ailments vary in the body, so equivalence cannot be established between them. Our view is that they are equivalent in the essence of the limb and its quality, so it is permissible to take one in exchange for the other, just as a healthy one is taken for a healthy one.

Section: A deficient limb may be taken in exchange for a deficient one if they are equal in that respect, such that what is cut from the perpetrator’s hand is like what is cut from the victim’s hand, because they are equal in essence and quality. As for if they differ—such that what is cut from the hand of one of them is the thumb, and from the other it is a different finger—retaliation is not permissible, because that would involve taking one finger for a different one. If the hand of one of them is missing one finger, and the other is missing that finger plus another, it is permissible to take the one missing two fingers in exchange for the one missing one finger. Is he entitled to the indemnity for his extra finger? There are two views regarding this. It is not permissible to take the other [fully intact] hand for it, because a complete [limb] is not taken in exchange for a deficient one.

Section: It is permissible to take a deficient [limb] for a complete one because it is less than his right. Is he entitled to take blood money for the fingers of the deficient [limb]? There are two views; one of them is that he is entitled to it, which is the opinion of al-Shafi‘i and the choice of Ibn Hamid. The second is that he has no indemnity along with retaliation, which is the school of Abu Hanifa and the analogy of Abu Bakr’s opinion, so that it does not lead to combining retaliation and blood money for one limb. The Qadi said: The analogy of his opinion is that retaliation is dropped, like his opinion regarding one whose hand is cut from the middle of the forearm, but that is not so, because he retaliates from the site of the injury and places the blade where the perpetrator placed it; he has the right to do that, just as if [the perpetrator] committed the crime against him above the موضحة (muwdihah - head wound exposing the bone), or if the head of the assailant was smaller, or if he took a paralyzed limb for a healthy one. This is distinct from [the case of] the cutter from the middle of the forearm, because he cannot retaliate from the site of the crime. This is how al-Sharif narrated it from Abu Bakr.