As written, I hear Mary Martin in Peter Pan saying "Clap your hands if you believe in fairies."

Instead, what about this: "You willingly suspend the disbelief being thrown up by one part of your mind so you can get something useful done in a different part."

Formulated that way, it covers fiction too.

See also: http://www.overcomingbias.com/2009/01/why-fiction-lies.html

http://www.overcomingbias.com/2009/01/a-tale-of-two-tradeoff...