Formalization of Natural Language Understanding

The understanding of natural languages on machines is one of the difficult topics in artificial intelligence. Based on the current theory, the formalization of natural language understanding is defined and its axiom system is improved in this paper. In this system, the two understanding types of 'meaning understanding’ and 'logic understanding’ are unified. According to the outputs from the execution of a prototype program for understanding chapters, the correctness and validity of all theoretical results presented in this paper are verified.