Prometheus was an expert systems shell designed by Expert Systems International in Oxford. It was based on Prolog with frames and forward- and backward-chaining rules added to make it easier for those unskilled at logic programming; it also had a tool for building graphical user interfaces. The book started off as a user manual and tutorial guide for this product. As far as I know, the software is no longer on sale, so the book is probably only of historical interest (as they say).
The name, incidentally, is only indirectly connected with the idea of bringing fire from heaven. It was bestowed during a company lunch in the George down Botley Road, when, while trying to decide on a name, one of the programmers noticed a "Prometheus" boiler next to the pub's fireplace.