Today's post, Extensions and Intensions was originally published on 04 February 2008. A summary (taken from the LW wiki):

You try to define a word using words, in turn defined with ever-more-abstract words, without being able to point to an example. "What is red?" "Red is a color." "What's a color?" "It's a property of a thing?" "What's a thing? What's a property?" It never occurs to you to point to a stop sign and an apple.

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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 Words as Hidden Inferences, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.

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