diagnosis a study of building a knowledge of specific issues, such as medicine or science. The purpose of this system is that a human expert consultation and answers about the issue. The
main purpose of this research is that we need to solve human problems. However, in practice, the system has to rely on human experts to provide basic knowledge in the first period. To this research requires a basic knowledge of the subject, whether it is a knowledge representation, reasoning and machine learning. An example of this is the pharmacist. Program MYCIN expert system for the diagnosis of disease or infected blood.