I don't think having no information about the other player is part of PD. If you do, then it's not academic at all- it's a key difference in a definitional distinction that is important!
After those 99 rounds have been played, is the game PD or isn't it?
Oh, and if you pick me to participate in the closest approximation of PD that you can provide, I will cooperate, take my reward (if any), and then explain that the differences between the approximation and actual PD were key to my decision- because I prefer to live in a world where cooperation happens in pseudo-PD situations.
After those 99 rounds have been played, is the game PD or isn't it?
No, it isn't. But someone who defects in ordinary PD might defect the last round in IPD for the same reasons. I certainly would.
[...] because I prefer to live in a world where cooperation happens in pseudo-PD situations.
You are looking for excuses instead of considering the least convenient possible world. Would you cooperate in this problem?
Today's post, The Truly Iterated Prisoner's Dilemma was originally published on 04 September 2008. A summary (taken from the LW wiki):
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