Michael Balter summarizes a new paper that found "IQ tests are measuring much more than just raw intelligence–they also measure how badly subjects want to succeed both on the test and later in life":
[T]he effect of financial rewards on IQ scores increased dramatically the higher the reward: Thus rewards higher than $10 produced g values of more than 1.6 (roughly equivalent to more than 20 IQ points), whereas rewards of less than $1 were only one-tenth as effective.
Another important finding:
By constructing a series of computer models of the data, the team found that higher motivation accounted for a significant amount of the differences in IQ scores and also in how well IQ predicted later success in life. For example, differences in motivation levels accounted for up to 84% of the differences between the boys in how many years of school they had completed or whether they had been able to find a job.
After reading the paper, Tyler Cowen concludes that "a) conscientiousness is more important than we think (when we think we are measuring the importance of IQ), and b) there are some smart people, smarter than we often think they are, and they pick and choose their spots."
For the right, this discredits a completely emotion- and culture-free measure of intelligence; for the left, it reveals how individual motivation, i.e. effort, is actually a core part of an individual's success. It's not random. And taking that individual's wealth away at higher rates than others is, in some respects, punitive of effort and motivation.
(Right now, of course, I support higher taxes for the successful. But not because of social justice – because we all need to sacrifice to get this debt under control.)
The Dish 