What did not make sense to me is that the prof says saying numbers backwards is highly correlated with intelligence but then the way we measure intelligence is by saying numbers backwards?<br><br>I.E. how do we know that people scoring high on the test are actually intelligent? That would depend on how we define intelligence and how ELSE empirically we can classify someone as intelligent.,(reply>), He explained how that works in the beginning of the interview: all cognitive tests correlate with each other + they correlate with everyday notions of intelligence + they correlate with good life outcomes (such as not dying early!).