... from none other than James R. Flynn -- the man who "did much to document" the Flynn effect and "promote awareness of its implications." There's really a lot of stuff in there, but here's something for you to taste:
... [T]he saddest result of the obsession with g [is this]: it makes the limitations of the concept no longer a matter of evidence. Any evidence that challenges the supremacy of g is not good evidence because it challenges the supremacy of g and that is that.
Note that we would not reason in this way in other areas. There is a musical g in the sense that whoever is better than me on the piano will probably outdo me on the organ. But skills could improve on one and not the other, and that would be of great significance to the world of music. There is a moral g in the sense that good people tend to be both more tolerant and more generous than the average. But over time, white Americans may have tended to become more tolerant of other races and no more generous in giving to charities. No black American would say that unless all of the components of moral g moved together, the trends were not significant.