IQ is only a good predictor when you compare low average and borderline (who indeed are at a disadvantage no matter their conditions) with average and higher.<p>Average, above average and higher scoring persons&#x27; outcome in life will depend more heavily on upbringing and surroundings than anything else.<p>In fact, those scoring the highest may actually end up worse - addiction, depression, anxiety, loneliness, etc. - all because they live well below their potential because of their circumstances...