Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good reference, not a play aid

With the GURPS Basic Set, Steve Jackson, the designer of GURPS, went a long way towards making a coherent magic system for a generic fantasy RPG. However, as Mr. Bonewits points out, it has little, if anything, to do with the way most people modern or past think about magic. Authentic Thaumaturgy is, if nothing else, an interesting read about the author's take on describing how a GM might design a "realistic" magic system for any game system, not just GURPS. He talks in depth about how people, past and present, view magic and how it really works, and points out that, for some, it really is a religion or way of life not to be taken lightly. The only real problem is that the book makes no real attempt to provide good examples of how that might be done for a full system -- it is left as an exercise for the reader.