Because humans are a sexually reproducing species, human brains are nearly identical. All human beings share similar emotions, tell stories, and employ identical facial expressions. We naively expect all other minds to work like ours, which cause problems when trying to predict the actions of non-human intelligences. 24 June 2008 [1]
Four days later:
Understanding the opposite sex is hard. Not as hard as understanding an AI, but it's still attempting empathy across a brainware gap: trying to use your brain to understand something that is not like your brain. [2]
Perhaps not incompatible claims, if the difference in men's and women's brains is small but significant. 'Nearly identical' is the point where the claims could be incompatible.
[1] http://lesswrong.com/lw/d1j/seq_rerun_the_psychological_unity_of_humankind/
[2] http://lesswrong.com/r/discussion/lw/d54/seq_rerun_the_opposite_sex/
The first quote you mention is the summary I wrote of "The Psychological Unity of Humankind". The full post contains this section:
...Let's go back to biology for a moment. What if, somehow, you had two different adaptations which both only assembled on the presence, or alternatively the absence, of some particular developmental gene? Then the question becomes: Why would the developmental gene itself persist in a polymorphic state? Why wouldn't the better adaptation win - rather than both adaptations persisting long enough to become complex?
So
Today's post, The Opposite Sex was originally published on 28 June 2008. A summary (taken from the LW wiki):
Discuss the post here (rather than in the comments to the original post).
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 2-Place and 1-Place Words, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
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