There are a lot of things that humans care about. Therefore, the wishes that we make (as if to a genie) are enormously more complicated than we would intuitively suspect. In order to safely ask a powerful, intelligent being to do something for you, that being must share your entire decision criterion, or else the outcome will likely be horrible.
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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 Leaky Generalizations, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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