evidence in every field of knowledge. Likewise, if it is established that there is no relevant difference between the case under consideration and the original case, this constitutes evidence in every field of knowledge. Wherever analogical reasoning cannot serve as evidence, neither can syllogistic reasoning. Abū al-Ma'ālī and the speculative thinkers before him neither follow nor approve of the logicians’ method. Rather, they reason from evidence which, in their view, entails its conclusions.

Nevertheless, the logicians and most speculative thinkers draw analogies between the unobserved and the observed whenever the shared attribute entails the ruling. Their examples include linking the two through a common definition, cause, condition, or evidence. Their opponents say:

“The ruling is not established for the unobserved because it is established for the observed. Rather, the universal proposition itself suffices to establish the point, without any need for analogy.”

The answer to them is:

“The same applies in matters of religious law. Whenever evidence establishes that the ruling is tied to the shared attribute, there is no need for the original case. The evidence establishing that the ruling is tied to that attribute is itself sufficient. Yet because this is universal, and a universal exists only in particular instances, identifying the original case provides a means of knowing that this universal is actually instantiated. This is useful in both legal and rational matters.”

Thus you know that whenever evidence establishes that the shared attribute is the basis of the ruling, or that the difference between the original case and the case under consideration is irrelevant, the analogy is sound and constitutes valid evidence, whatever its subject.

People have differed over what the term “qiyās” denotes. One group of scholars of legal theory, including Abū Hāmid al-Ghazālī and Abū Hāmid al-Maqdisī, maintains that it applies literally to analogical reasoning and figuratively to syllogistic reasoning. Another group maintains the reverse: it applies literally to syllogistic reasoning and figuratively to analogical reasoning—