The Second Approach: Rational Reasoning

This proceeds along three lines.

First: Drawing an analogy with urine already deemed unlawful. We say: these are urine and dung, and are therefore impure, like all other urine. This analogy requires demonstrating that the basis of the ruling in the original case is precisely its being urine or dung. This is indicated by the revealed texts, such as his statement:

“Guard yourselves against urine.”

And his statement:

“When urine came into contact with the garment of one of the Children of Israel, he would cut out the affected portion with scissors.”

The suitability of this rationale also supports it: urine and dung are foul and filthy, repugnant to people to a degree that calls for keeping clear of them. This accords with prohibition, encouraging people to cultivate noble character and wholesome habits. Its legal relevance is further supported by the impurity of the dung of creatures deemed foul.

Second: We say that, when we examine and investigate the dividing line between impure and pure substances, we find that, of the food transformed within animals’ bodies, whatever becomes part of the body is the wholesome portion, while whatever remains over is the foul portion. Hence it is called rajīʿ (returned matter): it is as though it was taken in and then returned—that is, sent back out.

Whatever foul matter emerges from the lower part of the body—such as faeces, urine, semen, wadhy (seminal fluid), and wady (post-urinary discharge)—is impure.

Whatever emerges from the upper part—such as tears, saliva, spittle, nasal mucus, and phlegm from the head—is pure. Whatever falls between the two, such as phlegm from the stomach, is subject to uncertainty.