We know the Vulcan philosophy comes from Surak, the Klingon way from Kahless, and that Zefram Cochrane is the posterboy for human exploration and ingenuity.
Where do the Rules of Acquisition come from?
Any Grand Nagus who comes up with a rule, really. Gint was supposed to be the original writer, but the rules have grown over the centuries - there's no way to know which ones were written by Gint.
So any Nagus could do whatever they want with the Rules, as long as they're accepted by the Ferengi people. In that episode, this is what Quark says, before he actually reads the new rules:
So since any Nagus can add their own wisdom to the book as a short, easily repeatable and rememberable sound bite, the Rules of Acquisition have simply grown over the years as the Naguses (Nagi?) add to it.
I also thought I remember Zek adding a 286th rule during the run of DS9, but I thought it was in Prophet Motive - it wasn't. Oh well.
They were first written ten thousand years ago by Gint, the first Grand Nagus.
Source: Memory Alpha, via DS9: "Body Parts".
P.S. According to DS9, they may have been more of guidelines than rules, but this isn't certain (could be Quark's imaginings).