Shaykh al-Islām—may Allah have mercy on him—said:

Section: Attributing a Single Ruling to Two Causes

This also concerns analogous questions, such as the existence of a single effect within the power of two agents, and a single act proceeding from two agents. We say:

Although disagreement over this is well known, most jurists, both of our school and others, allow a ruling to be attributed to two causes, while many jurists and theologians disallow this.

The disagreement ultimately amounts to variation in approach and wording, rather than mutually contradictory positions. A parallel is the disagreement over whether a cause admits exceptions. There is well-known disagreement about this among all the various groups, both within our school and outside it; indeed, two positions on it are reported from Ahmad.

The underlying point is that the term “cause” may mean a necessitating cause: a complete cause from which the ruling cannot fail to follow. Such a cause cannot conceivably admit exceptions; whenever a counterexample arises, it is invalidated. It includes what is called a constituent of the cause and a condition of the ruling;