Adam, to my visiting neighbor: Red and blue make purple.
Neighbor: That's right! You're so smart. How did you know that?
Adam: Darth Vader and Obi-Wan.
Me: Umm . . you know red and blue make purple because of Darth Vader and Obi-Wan?
Adam: Darth Vader's lightsaber is red, and Obi-Wan's is blue, and when they hit . . .