Xu Guangqi (1562–1633)
In all studies, there is theory and there is application. The benefit of this work is that it helps those who study theory to forego facile knowledge in favour of concentration and focus. In addition, it helps those who learn application to identify the rules and apply them using their own ingenuity. That is why everyone should study it. I hear that, in the West, there is a university with a long history and it is attended regularly by hundreds and thousands of students. They all have to show a good grasp of this work before they are admitted. Why? To ensure that they can think and reason clearly and precisely. That university has nurtured many famous scholars.