Correct me if I'm wrong, but (1) and (2) and (4) all seem to come from a place of believing that if a test is not 100% accurate then it is useless. Hopefully wh

Correct me if I'm wrong, but (1) and (2) and (4) all seem to come from a place of believing that if a test is not 100% accurate then it is useless. Hopefully when I phrase it that way you can see why none of these objections "kill the validity of IQ tests dead". (3) is very interesting and there is not yet any agreement as to what is causing it. Flynn seems to have thought our culture is slowly becoming better at training us to think abstractly. There's some evidence for this: one Australian study found that over 20 years the students in a set of schools became better at a vocabulary test but did not improve at all in processing speed. This is not what you would expect to see if the improvements were due to better nutrition or less environmental lead. For (5), haven't read it. He's stunningly erudite and a careful author though, it's worth taking him seriously. Do you have some examples of points he raised?