analogical reasoning and syllogistic reasoning are equivalent, differing only in the particular material employed. If that material yields certainty in one, it yields certainty in the other; if it yields conjecture in one, it yields conjecture in the other. Syllogistic reasoning consists of three terms: the minor, the middle, and the major. Its middle term is what, in analogical reasoning, is called the effective cause, the basis of the ruling, and the common attribute.

Thus, concerning nabīdh, someone may say: “Every nabīdh is intoxicating, and every intoxicant is forbidden.” He must establish the major premise; only then is the demonstration complete. He can then say: “Nabīdh is intoxicating, so it is forbidden by analogy with grape wine, because both share the property of causing intoxication.” Intoxication is the basis of the prohibition in the original case, and it is also present in the case under consideration. The same evidence that establishes that every intoxicant is forbidden establishes, with even greater force, that intoxication is the basis of the prohibition. Indeed, making distinctions in analogical reasoning is easier for him, since the original case provides evidence for prohibition, and the ruling is therefore already known to hold in some particular instances.

In analogical reasoning, it is not enough to establish the ruling in one of the two cases on the grounds that it holds in the other merely because they share an attribute for which no evidence has established that it entails the ruling—as some mistakenly suppose. Rather, it must be known that their shared attribute entails the ruling; and this shared attribute is the middle term. Jurists and scholars of the principles of jurisprudence call this “the demand to establish the attribute’s effect on the ruling.” This is the most significant objection raised against an analogy, and answering it is generally what is needed