Shaykh al-Islām—may Allah sanctify his soul—said:

Section: On setting out the general principles of “logic” and its flaws

They constructed it on the premise that the means of acquiring knowledge are confined to “definition” and related forms, such as descriptive definition and the like, and to syllogism and related forms, such as induction and analogy. For knowledge is either “conception,” which is knowledge of individual concepts, or “assent,” which is knowledge of the relations between them through negation or affirmation. Each of these two kinds of knowledge is either “self-evident,” requiring no method of acquisition, or “inferential,” requiring such a method. The method for acquiring conceptions is “definition,” while the method for attaining assent is “syllogism,” which they call demonstration if its premises are certain.

They then said: “Definition” is an expression indicating the essence of a thing, although it may also refer to the thing defined itself, just as a name is an expression indicating the thing named and may also refer to the thing named itself,