It's a test of the universal law that two random different things are never miraculously equal and never equal unless there is a spectacularly good reason.
That's not a universal law. A random partition of a large set of objects may well produce two sets in which the distribution of all properties is the same as in the original set. The same is true if the set is partitioned according to some property that doesn't correlate with anything else.
The controversies on this issue are about whether certain properties that can be used to partition human populations do have correlations with various other relevant properties, what is the reason for these correlations if they do exist, and what should be their wider implications.
Today's post, Why Are Individual IQ Differences OK? was originally published on 26 October 2007. 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 No One Knows What Science Doesn't Know, and you can use the sequence_reruns tag or rss feed to follow the rest of the series.
Sequence reruns are a community-driven effort. You can participate by re-reading the sequence post, discussing it here, posting the next day's sequence reruns post, or summarizing forthcoming articles on the wiki. Go here for more details, or to have meta discussions about the Rerunning the Sequences series.