The first code was amended 14 years after it was created, and by 1892 (R&A, prior to any American code) the rules had grown from 13 to 40, with an additional 14 special rules for medal play and 10 more for etiquette. The first clubs created their own codes which were really no more than a couple of handfuls of rules describing their interpretation of the principles of the game, and when you think about it, that 'method' could still be used today by any club who wished to go down that road, although golf would never have expanded if rule making remained in the hands of various fiefdoms, it needed a cohesive set of Rules that encompassed the many different situations that would arise once the game left the seaside.
The early rule makers knew what Richard Tufts wrote a couple of hundred years after the first code was written:
"These basic principles (of golf) fortunately are simple, logical, practical and expressive. By their recognition and by their application to specific Rules, it is possible to bring warmth and an understanding to the austerity and complexity of the Rules.
The one serious warning that must be made is that these principles can never become an adequate substitute for the Rules themselves. The more exact descriptive wording of the Rules is essential to provide adequate answers to the many complicated questions that arise in the play of the game."
So, if Tufts is correct we are still playing the game by a centuries old set of principles, and we use those principles to create rules as they are needed, the same as was done from the very start.