For What One Piece Stand For ? here a theory
well i was thinking about One Piece really is..
as we have see the main subject of the manga is tha 100 years of lost History.
We see that every city that have a the Tablet of the Ancestor is very rich (like at Sky Island).
Also i believe that the person that is very near at One Piece is Luffy as we read from the manga only Gol D Roger have gone at Sky Island before and read the tablet.
We haven't seen anything about WhiteBeard and the Lost History.
i Believe that everything that Gol D Roger achieved it was from 100 years of lost history.
in one chapter i read that Roger execured without Reason and now we wee that Goverment executed and still execute everyone that know something about lost history.
Also after Roger only Robin have read 3 tablet of the ancestors.
Post your opinions ;)