If there's one thing in the field of psychology that is actually science, it's IQ tests. Empirically, IQ has been shown to not change much at all over time, and

If there's one thing in the field of psychology that is actually science, it's IQ tests. Empirically, IQ has been shown to not change much at all over time, and is the single most reliable factor for predicting outcomes that psychology has ever produced. The big 5 personality model is the next best tool psychologists have, but it's not nearly as reliable as IQ. That said, it's still not an excellent measure for basing predictions on, by the standards of "traditional" science. But if you don't put any weight in IQ, then there's nothing in the entire field that you should have any faith in.