The Blue Elephant Principle
This is an easy to understand principle based on the well known children's 'pink elephant' conundrum.
Child A: I know something you can't do.
Child B: What?
Child A: Don't think of a pink elephant.
Child B: ...
Child A: I know something you can't do.
Child B: What?
Child A: Don't think of a pink elephant.
Child B: ...