If something indicates which alternative took place, Rule A applies, and if Rule A applies, the distinctions we make between alternatives are distinctions that Nature also makes. They correspond to something in the real world. On the other hand, if nothing indicates which alternative took place, Rule B applies, and if Rule B applies, the distinctions we make between alternatives are distinctions that Nature does not make. They correspond to nothing in the real world. They exist solely in our minds.

One Bounce by Eric J. Heller. Here we see a quantum wave associated with an electron. The wave starts out orderly from the top, bounces off of a rough barrier (the "mountain" at the bottom) in the presence of a graviational potential, and reaches its former average height at the moment the image was recorded, i.e., after one bounce.