Was reminded of this brilliant summary of the role of myth and legend by Terry Pratchett yesterday.
"You're saying humans need ... fantasies to make life bearable."
"NO. HUMANS NEED FANTASY TO BE HUMAN. TO BE THE PLACE WHERE THE FALLING ANGEL MEETS THE RISING APE."
"Tooth fairies? Hogfathers?"
"YES. AS PRACTICE. YOU HAVE TO START OUT LEARNING TO BELIEVE THE LITTLE LIES."
"So we can believe the big ones?"
"YES. JUSTICE. DUTY. MERCY. THAT SORT OF THING."
"They're not the same at all!"
"REALLY? THEN TAKE THE UNIVERSE AND GRIND IT DOWN TO THE FINEST POWDER AND SIEVE IT THROUGH THE FINEST SIEVE AND THEN SHOW ME ONE ATOM OF JUSTICE, ONE MOLECULE OF MERCY. AND YET YOU ACT, LIKE THERE WAS SOME SORT OF RIGHTNESS IN THE UNIVERSE BY WHICH IT MAY BE JUDGED."
- (Capitals because I've cut and pasted from the text online rather than write it all out myself - one of the characters in this discussion is Death who always peaks in caps. The other is his granddaughter, Susan.)