A comparison of the absolute coordinates used in space reference by sixteen Austronesian languages makes it possible to propose a hypothesis regarding the geocentric system of Proto-Oceanic: on land, one up-down axis defined by the declivity of the ground; at sea, a second up-down axis motivated by the prevailing trade winds. After reconstructing the system of Proto-Oceanic, we model the principal paths of evolution that derived from it historically and led to the diverse systems attested in modern Oceanic languages.