Even Edward Thorndike, who fashioned our modern education system around the notion that if you are good at one thing, then you are good at most things, conducted his own research to examine the correlation between school grades, standardized test scores, and success at professional jobs. He also found weak correlations between all three—yet he still rationalized that he could safely ignore this fact because he believed in a hypothetical (though unproven) one-dimensional “learning ability” that undergirded success in both school and work.
