Originally Posted by PoiuyWired
look at Vader/Anakin in the end.
That add-in with Christensen as the ghost of Vader was a stupid idea. Some say that they did that because that's what he looked like when he was "still good", but that takes away from the fact that he was redeemed at the end.
But anyway, that's a bit off-topic. But yea, Qui-Gon had learned how to do the whole Force Ghost thing and he then taugh Yoda, who then taught Obi-Wan.