What are the conditions for the validity of an exception (Istithna) in a statement?
General Chapter
Al-Mughni
Book of Acknowledgment of Rights
Primary text
An exception is only valid if it is connected immediately to the preceding statement. If the speaker pauses long enough for speech to occur during the pause, or if an extraneous statement separates the excepted item (mustathna minhu) from the exception (mustathna), the exception is invalid. This invalidity arises because if a pause occurs or the speaker turns to another topic, the ruling established by the initial affirmation becomes fixed and cannot then be negated.
Supporting text
If the exception is made during the course of the initial statement, the ruling of the affirmation does not become fixed, and the statement awaits completion, as the exception, condition, conjunction, substitution, or similar elements are then intrinsically linked to the main declaration.