we reply: Phlegm from the stomach—if it is held to be impure—is a normal occurrence, as is wind.

We also ask: Why do you say that the determining factor is the outlet? Why should it not instead be the origin and transformation of the substance? Whatever is formed in the upper body would then be pure, and whatever is formed in the lower body impure. Semen emerges from between the backbone and the ribs, unlike urine and post-urinary discharge. This criterion is more consistent: vomit and phlegm deemed impure both emerge from the mouth, yet they are impure because they have undergone transformation in the stomach. We shall also explain the distinction, if Allah Most High wills.

As for the fifth argument, their assertion that semen is transformed from blood and that transformation does not render a substance pure admits of several clear and decisive answers.

First, it is refuted by the human being and the embryonic lump of flesh: both arise through transformation from it, and thereafter from the clot, which is blood. Yet no one has held the human being to be impure. The same applies to all animals whose flesh is lawful to eat.

Second, we do not concede that blood is impure before it appears and emerges from the body. Evidence must therefore be provided for declaring it impure. An analogy with blood after it has appeared and emerged, based on their being the same substance, is insufficient. For we say that there are several grounds establishing its purity:

First, what is impure is that which is regarded as foul and repugnant, and this description does not apply