A hypothetical safety rule prohibits storing a particular chemical in a closed room because it creates a serious respiratory hazard. Someone proposes applying the same precaution to another material that genuinely creates the same hazard.
The first material is the asl, the second the far, the original rule is the prohibition, and the proposed effective cause is the shared danger. If no such danger is established in the second material, similar packaging or color cannot substitute for an effective cause. This is a nonreligious safety example illustrating the structure of analogy.