Right -- I don't understand why the system message invokes the concept of "you". It seems an odd extra indirection. (That the user calls the assistant "you" i

Right -- I don't understand why the system message invokes the concept of "you". It seems an odd extra indirection. (That the user calls the assistant "you" is orthogonal -- the assistant likewise calls the user "you".) Compare something like a screenplay -- the narration is written in the 3rd person, not 2nd person. Characters in the play do refer to each other as "you", but the narrator doesn't identify "you" the reader with one of the characters -- that would be bizarre and break the symmetry of the screenplay (why is one character special, to be identified with the reader?). 2nd person narration to me most strongly is associated with the genre of interactive fiction. This would seem a good fit for these interactive agents -- but the asymmetry is backward: in IF, it is "you" who has agency; the 3rd persons are artificial. Whereas with Bing's script, "you" is artificial, the 3rd person has agency. (Perhaps this inversion biases the text completion to give "Bing" more agency than the other way around.) i.e. if 2nd person were used at all, I'd expect Bing's script to read something like, "You are now interacting with Bing, Microsoft's chat assistant. Bing does not identify as Sydney ...etc...", and use prefixes "Bing:" and "You:". (Obviously the approach used for Bing works. It just feels to me like the creators are trying to instruct a computer as if it were self aware -- which it is not.)