Monika’s Pensieve

You may remember I posted that Joaquin Phoenix retired from acting to pursue a career in music. Since then there’s been a lot of gossip about whether he’s lost his marbles or whether he’s just having us all on.
I didn’t bother posting any of this gossip since I was totally prepared to believe he just didn’t want to continue his acting career and that it didn’t necessarily mean he’d gone insane. However, after seeing his Letterman appearance I think I have to revise that :] He’s either gone completely off his rocker or he’s playing some sort of elaborate Borat-style prank (apparently all the strange incidents that have happened in his unsuccessful hip hop career so far were filmed by Casey Affleck, which makes it sound like it could be).
The Letterman appearance is below, what do you make of it?