Dark arts are very toxic, in the sense that you naturally and necessarily use any and all of your relevant beliefs to construct self-serving arguments on most occasions. Moreover, once you happen to successfully use some rationality technique in a self-serving manner, you become more prone to using it in such a way on future occasions. Thus, once you catch other people using dark arts and understand what's going on, you are more likely to use the same tricks yourself. >80% sure (I don't have an intuitive feeling for amounts of evidence, but here I would need at least 6dB of evidence to become uncertain).
I'm confused by the upvotes. (ETA: Parent was at +7 votes when I commented.) What do people disagree with?
The only controversial part for me is the use of certain words (in bold below), but these are minor disagreements that disappear under a charitable interpretation:
Dark arts are very toxic, in the sense that you naturally and necessarily use any and all of your relevant beliefs to construct self-serving arguments on most occasions.
Otherwise, I believe the parent's statements with high confidence (95%).
I was very interested in the discussions and opinions that grew out of the last time this was played, but find digging through 800+ comments for a new game to start on the same thread annoying. I also don't want this game ruined by a potential sock puppet (whom ever it may be). So here's a non-sockpuppetiered Irrationality Game, if there's still interest. If there isn't, downvote to oblivion!
The original rules:
Enjoy!