Originally posted by: frendon
force "ghosts" only show themselves in the form they are most comfortable with. They are not a physical entity any more, they are pure spirits they have no real image, they left their physical bodies and now are pure energy, Obiwan and Yoda show themselves as their old selves because that's how Luke knew them and they are comfortable with that image, is just a visual representation of what they once were
<Morpheus> It's what George Lucas might call "residual self image." </Morpheus>
But seriously, I think the only way Hayden at the end of ROTJ would have worked is if they would have had him replace Shaw in the unmasking scene too. Two actors playing the same character within the same 10 minutes just doesn't sit well with me.