C3P0 has obviously had his memory of the events of Episodes 1-3 erased, but there is no reason to believe R2D2 has. He is a mechanic, he responds to queries and notifies his owners of danger, but he doesn't make conversation. I think he knows everything. Yes, obviously. <{POST_SNAPBACK}> I think a lot of people had their memories erased, look at how badly the technology degraded from episode one to episode four. I know, it's because the filmmakers had better stuff, but if I had been in charge, the technology would have looked less advanced in the earlier movies, or at least about the same, not better. <{POST_SNAPBACK}> The degradation of technology could be explained by the totalitarians Emperors lack of concern for anyone for himself. That's my thought although I could be full of Sith. Sorry, couldn't help myself.