Let's say person A picks up a pencil and drops it and person B catches it.
I think most people would agree that person A dropping the pencil allowed person B to catch it, but did not cause person B to catch it. I think we can also agree that person A dropping the pencil both caused the pencil to fall, and allowed the pencil to fall.
Based off of this one example, I would think that if X causes Y, then X allows Y. (That is, causing is a subset of allowing.) However, I'm not sure when something causes something else to happen rather than just allowing it to happen, and I'm curious as to where this line is drawn.
How do I tell if something causes something else to happen, and how do I tell if something allows something else to happen?