There is a commonly held misconception about computers underlying current software engineering methodologies.
Humans deal with information.
Conceiving computers as data processing machines provides a realistic framework for assessing their capabilities. We will demonstrate in what ways the capabilities of computers and humans differ. This becomes seriously problematic if the same expression is used for the understanding of both the computer's capability and of the human expertise. But the view of humans as information processing systems is widely held in the society at large, not only within the expert systems community. Consequently, we also have to revise our concepts of human expertise.