Quote Originally Posted by ChrisIII View Post
Before the prequels I think it was mostly assumed by the fans that Vader or Palpatine didn't know Yoda directly, although Yoda seems to at least have some knowledge of Anakin.

There's even one passage in the ROTJ novel that seems to imply Palpatine doesn't seem to know Yoda.


“So tell me, young Skywalker—who continued your training?”
That smile, again, like a knife. Luke held silent, struggling to regain his composure.
The Emperor tapped his fingers on the arm of the throne, recalling. “There was one called … Yoda. An aged Master Jedi … Ah, I see by your countenance I have hit a chord, a resonant chord indeed. Yoda, then.”
"This Yoda," the Emperor mused. "Lives he still?"

Luke focused on the emptiness of space beyond window behind the Emperor's chair. The deep void, where nothing was. Nothing. He filled his mind with this black nothing. Opaque, save for the occasional flickering of starlight that filtered through the ether.

"Ah," cried Emperor Palpatine. "He lives not. Very good, young Skywalker, you almost hid this from me. But you could not. And you cannot. Your deepest flickerings are to me apparent. Your nakedest soul. That is my first lesson to you."
I'm not seeing how that implies he doesn't know Yoda. He's toying with Luke, playing at uncertainty so that Luke won't be sure exactly how much he does or doesn't know. Hell, if anything, the very deliberate phrasing "Lives he still?" could easily be read as Palpatine mocking Yoda's standard speech pattern.