If humans were perfect reasoners, your objection would be valid. But people are irrational, and will tend to over-discriminate based on race if minor discrimination (based on the amount of info race does provide) is socially allowed.
Here's a thought experiment: have a bunch of typical humans guess the intelligence of a group of subjects, knowing their test scores, grades, and job performance, but not race. Then have the same judges guess the intelligence of a second group of subjects, using all the above info plus race, and the fact that "on average, whites are smarter than blacks" without any quantitative data on by how much*. I consider it likely that the second group, despite having more information, will be less accurate than the first. Therefore, if race-based IQ differences exist, we should try to ignore them unless we know their magnitude and are confident in our own rationality.
people are irrational, and will tend to over-discriminate based on race if minor discrimination (based on the amount of info race does provide) is socially allowed.
What will happen at various degrees of minor discrimination not being socially allowed?
Today's post, Why Are Individual IQ Differences OK? was originally published on 26 October 2007. A summary (taken from the LW wiki):
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