On first listen Kendrick Lamar's To Pimp A Butterfly seemed to contain a ton of mysteries that needed unpacking. To whom exactly does the butterfly/caterpillar parable pertain? How did he get that Tupac interview? Is he really okay with forgiving Michael Jackson's child molestation charges because of "Billie Jean"? In the weeks after its release, we've come to learn more about the album (including which song K Dot would've featured Pac on), and today, a new wrinkle presents itself. 

In addition to the Tupac tidbit, another thing Kendrick shared during his Mass Appeal interview was the fact that TPAB's physical copies feature hidden braille inside. Complex spoke with a teacher of the visually impaired, and she said the message translates to "A Kendrick By Letter Blank Lamar." They guess that he meant it to read "A Blank Letter by Kendrick Lamar," which makes sense when you consider that good kid, m.A.A.d city's subtitle was "A Short Film By Kendrick Lamar." Check out a picture of the inside packaging in the gallery above.