You can avoid a Happy Death Spiral by (1) splitting the Great Idea into parts (2) treating every additional detail as burdensome (3) thinking about the specifics of the causal chain instead of the good or bad feelings (4) not rehearsing evidence (5) not adding happiness from claims that "you can't prove are wrong"; but not by (6) refusing to admire anything too much (7) conducting a biased search for negative points until you feel unhappy again (8) forcibly shoving an idea into a safe box.
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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 Affective Death Spirals, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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