The  Arthur R. Jensen Telegraph obit Steve Sailer mentioned below features this photo of Jensen  standing in front of blackboard during a lecture at University of California, Berkeley, in 1970. I thought "there`s that "Bell Curve" of which we've heard so much. Uh-oh—it`s two bell curves."

The one one the right represents a group (call it x) with an average of something (let us say IQ points) of 100. The one one the left represents a group (call it y) with an average of 85.

And that`s what`s caused all the trouble. If the cover of Charles Murray`s book had had two Bell Curves on it, it would have been burned.