To: PoPa Bar Abba
And what do you think the guys who wrote the treatises read?
You do realize that the Shulhan Arukh is mere a “restatement” based on the case law, designed for those lacking the competence to read the originals. In a system based on “common law” (meaning cases, as opposed to decrees and codes – which include both Jewish and common law), all law goes back to previous decisions. Note that in “code” systems such as Roman law, you read the code and decide for yourself what it means today based on original intent and your understanding – past practice counts for little.