the reasoning system by knowledge activation of the present invention stores shallow knowledge and deep knowledge in memories . the reasoning by the reasoning mechanism is executed using the shallow knowledge . in case of the shallow knowledge to be used in the reasoning is not stored , the deep knowledge is used in the execution of the reasoning . based on the information which is obtained by the execution of the reasoning , shallow knowledge is newly acquired . the reasoning system by knowledge activation needs only a short time for reasoning . even in the case where shallow knowledge which is necessary for fast reasoning is not stored , the execution of the reasoning is possible , and new shallow knowledge is easily obtainable .