The present paper is an introduction for the RT-11 Prolog(Edinburgh version), a logical program language developed by A. I. Department of Edinburgh University, on the LSI-11 minicomputer system in our laboratory. We introduce a small Prolog program as an example, which describe the family relation ship of the cats in my house. In this program, we use English sentences to communicate with the computer system as if the computer understood English. We are now in preparation for the further complicated Prolog program in order to control a psychological experiment using a natural language.
