 And that is high level of mathematics. In fact, when they came in Africa, what happened is they saw those structures and they say, this is a disorder structure. But later on, it happened to be a main subject in mathematics called fractal. So, we have lost the purpose of mathematics in our continent. And when we do mathematics, we do it with the purpose of having a lot of theorem in our mind. But the question is, how useful are those theorems? How useful are those formulas if we cannot apply it to solve the problem in our continent?