First of all, the IQ of normal people is not much different, but people's background, experience, mentality and personality are very different. In mathematics alone, when you encounter difficulties in your study, don't let naive IQ take the blame. Learning mathematics is a tiring job, with complicated calculations and endless thinking, so many people will shrink back, be lazy, fall behind for a long time, lose interest in learning, and then complain. That's how the theory of mathematical uselessness came about. Moreover, mathematics itself is a technical activity, which is not as difficult as imagined. All the achievements in mathematics are obtained through endless calculation, practice and practice. If there is no production and life, then mathematics will not exist, and any knowledge of mathematics is beyond the imagination of any talented mathematician. Finally, to quote a classic, Newton said that he made achievements on the shoulders of giants, so it is impossible for us to understand and master all the mathematical achievements left by countless predecessors in a few years. Therefore, we will find mathematics difficult. In fact, mathematics is not difficult, just more and bigger. Just like the universe, we can't fully grasp it, but we can't give up our persistent scientific research spirit, as long as you are willing to drill.