I was reading in one of Hawking's books about how the trajectory of a large object differs from a small object. Newtonian physics vs quantum physics. I believe they used the example of someone kicking soccer balls through slits in a wall and recording where they landed.
Then imagined shooting a smaller particle through the same slits and noticing the difference in dismemberment.
RE: 1918: Surely You’re Joking, Mr. Feynman!