If you think that the apocalypse will be in 2020, while I think that it will be in 2030, how could we bet on this? One way would be for me to pay you X dollars every year until 2020. Then, if the apocalypse doesn't happen, you pay me 2X dollars every year until 2030. This idea could be used to set up a prediction market, which could give society information about when an apocalypse might happen.
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This post is part of the Rerunning the Sequences series, in which we're 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 You Can Face Reality, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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