Forgetting and Update -- an exploration

Knowledge Update (respectively Erasure) and Forgetting are two very different concepts, with very different underlying motivation. Both are tools for knowledge management; however while the former is meant for accommodating new knowledge into a knowledge corpus, the latter is meant for modifying – in fact reducing the expressivity – of the underlying language. In this paper we show that there is an intimate connection between these two concepts: a particular form of knowledge update and literal forgetting are inter-definable. This connection is exploited to enhance both our understanding of update as well as forgetting in this paper.