Bracton studied the form of the original writs. He procured, for his own use, complete transcripts of the pleadings in selected cases. These were used to write his treatise on the law. He was also the first to offer commentary on the cases he wrote about. In this way Bracton was modern; he criticised and praised various decisions. He called those who were a generation before him, his "masters". The cases he wrote about were at least twenty years older than his book. His writing is not like a modern legal treatise comparing case results. There is no concept of case law as one would find in a modern text book. He selected cases and wrote a general description of what the law should be in a given set of circumstances. There was no real stare decisis. He gave descriptions of what the decision should be in hypothetical fact situations, without mention of actual cases. He also included many sample writs for various situations. Bracton chose cases based on his admiration for the judges involved, and wanted to make exemplars of their logic. The inclusion of case law was important, because it was the first time this had occurred in English legal writing. Lawyers for two centuries (thirteenth and fourteenth centuries) were introduced to the concept of case law and legal logic by Bracton's book. A new and modern course was set.