Here's a long, somewhat philosophical discussion I had on Facebook, much of which is about cryonics. The major participants are me (Tanner Swett, pro-cryonics), Ian (a Less Wronger, pro-cryonics), and Cameron (anti-cryonics). The discussion pretty much turned into "There is no science behind cryonics!" "Yes there is!" "No there isn't!"

As you can see, nobody changed their minds after the discussion, showing that whatever the irrationality was, we were unable to identify it and repair it.