ITS and ILEs are often discussed as if they were they were the only two distinct approaches to developing knowledge-based systems for education
On the surface, this paper -- discussing first ITS then ILEs -- perpetuates that image
However, on a more careful reading, it should be apparent that a field which began with two relatively clearly opposing positions has now begun to fracture into a multitude of related systems and approaches
Instead of two points of view on the application of artificial intelligence to education, it is more accurate today to see the field as a continuum, with omniscient, tutor-controlled ITS on one end, and completely student-controlled ILEs on the other
The continuum represents a variety of different ways of dealing with the problems and weaknesses of the two