All of this is true because it rhymes.
5 seconds sound clip from the The Lego Movie (2014) movie soundboard.
You can hear this line at 00:02:01 in the Blu-ray version of the movie.
Quote context
[...]
- About the Piece of Resistance.
- Oh, yes! The supposed missing Piece of Resistance that can somehow magically disarm the Kragle.
- And with a noble army at the helm, this MasterBuilder will thwart The Kragle and save the realm.
- And be the greatest most interesting, most important person of all times.
- All of this is true because it rhymes.
- Oh, wow. That was a great, inspiring legend that you made up.
(VITRUVIUS YELLING WHILE FALLING)
- A Special One? What a bunch of hippie-dippie baloney.
[...]