50. A knowledge engineering tool comprising a computer system having a stored program and memory for storing a knowledge base, said knowledge base including control knowledge, factual knowledge and judgmental knowledge, said judgmental knowledge including judgmental rules having premises for limiting the conditions in which the rules are applicable and conclusions for indicating the actions to perform when the rules are successfully applied, a built-in control procedure providing a base-level of control of the system, points of articulation in said built-in control procedure to allow the execution of specified portions of the control knowledge when said points are reached, and a control program for producing system activities in accordance with said built-in control procedure and said control knowledge by interpreting and executing said built-in control procedure and said control knowledge, whereby said control knowledge can be separated from said factual knowledge and judgmental knowledge and stored as a distinct portion of the knowledge base.
50. A knowledge engineering tool comprising a computer system having a stored program and memory for storing a knowledge base, said knowledge base including control knowledge, factual knowledge and judgmental knowledge, said judgmental knowledge including judgmental rules having premises for limiting the conditions in which the rules are applicable and conclusions for indicating the actions to perform when the rules are successfully applied, a built-in control procedure providing a base-level of control of the system, points of articulation in said built-in control procedure to allow the execution of specified portions of the control knowledge when said points are reached, and a control program for producing system activities in accordance with said built-in control procedure and said control knowledge by interpreting and executing said built-in control procedure and said control knowledge, whereby said control knowledge can be separated from said factual knowledge and judgmental knowledge and stored as a distinct portion of the knowledge base. 55. A knowledge engineering tool as set forth in claim 50 wherein said factual knowledge includes definitions of classes and said points of articulation include at least one point where an instance of class is created.