As for its necessitating purification from ritual impurity, that is true. However, the causes requiring such purification are not confined to impure substances. Minor ritual purification is required after passing wind, by consensus. The evidence also establishes that it is required after touching with desire, touching the private parts, eating camel meat, apostasy, and washing the deceased. In the early days of Islam, it was also required after eating anything cooked over fire. None of these causes is itself impure.

As for major ritual purification, it is required after penetration, when the two circumcised parts meet, even without any impurity. It is also required, according to a preferred view, after childbirth unaccompanied by bleeding, although the child is pure. It is required upon death, although the deceased is not deemed impure. According to some scholars, it is also required upon embracing Islam.

Their statement, “Whatever necessitates purification from ritual impurity, or requires a ritual bath, is impure,” is therefore contradicted by these numerous cases and does not hold universally. If they add to the effective cause the condition that it be something discharged from the body, wind and a newborn child provide decisive counterexamples.

Furthermore, it may be said: Your qualification “discharged” is merely an incidental attribute and cannot therefore be used to exclude counterexamples.

The converse is also false, and the attribute has no bearing on the ruling. Many things that do not necessitate purification from ritual impurity are nevertheless impure, such as blood that has not flowed and a small amount of vomit. Moreover, the distinction will be explained later, if Allah Most High wills. These, then, are three or four grounds of rebuttal.

As for their statement, “The purification required because of it is more far-reaching than cleansing the substance itself,” this conflates two unequal things