Nowadays, there are many expert systems being used in many domains such as in healthcare, legal and financial.
In the 80s, most of the expert systems have been purely rule-based before a new paradigm for reasoning was introduced at Yale University called the Case-Based Reasoning (CBR).
In this study, we used the Case-Based Reasoning (CBR) for reasoning.
CBR is a paradigm for reasoning from the solutions of previous cases.
CBR has a memory model that organizes and maintain past cases and a process model for retrieving and modifying old cases and assimilating new ones.
Thus, the CBR-based expert system can identify the type of disease using the experiences of previous case that stored as a case base.