Yes, high scores in intelligence reliably point to higher intelligence. One of the signs of high IQ in adults is that they typically perform well on IQ tests. While 95% of people have IQs ranging from 70 to 130, exceptionally intelligent people score over 130. Those who score more than 145 are in the top 1% of intelligent people. Also note that while high IQ scores are universal measures of human intelligence, they also suggest a highly motivated mental state to take the test. So, a smart person who is unmotivated (maybe due to their age) can have a low IQ and still be a genius. We may also tell if a person is intelligent without knowing their IQ test scores. For example, lower-intelligence persons mostly learn from their successes. While high-intelligence people learn from both their failures and their successes in life.