I don't understand what makes learning about cognitive biases intrinsically different from obtaining any other type of knowledge. That is, couldn't you make a parallel argument that learning math (or any rationality skill) is dangerous unless it is applied evenhandedly to your own beliefs and to the beliefs of others?
The problem is that it's much easier to apply knowledge about biases to dismiss people who disagree with you as biased then to apply knowledge about math to...I'm not even sure what the analogous thing you're thinking about is.
Today's post, Knowing About Biases Can Hurt People was originally published on April 4, 2007. A summary (from the LW wiki):
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