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?
I'm not in an abstract game. I only play games with some concrete aspect. If you asked me, on the street, to play a game with a stranger and I recognized the PD setup, I would participate, but I would not be playing prisoner's dilemma- I would be playing a meta-version which also has meta-payoffs.
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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This post is part of the Rerunning the Sequences series, where we'll be going through Eliezer Yudkowsky's old posts in order so that people who are interested can (re-)read and discuss them. The previous post was The True Prisoner's Dilemma, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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