Read the original article, and make a point of making it all the way to the end. It seems like many of the commenters who are popping off at Murray haven't really read him. He doesn't discount motivation at all, and he very narrowly defines what IQ means to someone's life. It's a simple fact that some people will never be PhDs in orbital mechanics no matter how hard they try. Better they should try for something that they can do.
d.o.l.
Criminal Number 18F
How many PhD's in orbital mechanics does one really need? School is not the only place where one can get an education. Many educated in the "school of hard knocks" learn to do quite well.