Jan Ferdynand Nax (April 1736 – 19 January 1810) was an architect, economist, social reformer and adviser on the navigability and conservation of Poland's water resources.
While he was born in Gdańsk, and was of German origin, Nax spent most of his life in Poland and was strongly assimilated into Polish society.
[1] As an economist, Nax based his thinking around the theory of mercantilism, which generally supported the development of a monetary-based economy instead of the system of servitude which then existed in Poland.
Nax supported the development of trade and production, stressed the need for reform in agriculture, and promoted enfranchisement of the peasant class.
Nax conducted studies of Poland's major waterways, including the Pilica and Warta rivers, drafted a map of the Dniester River (1781); and wrote regulations for the Bug, Narew, Nida, Pilica and Wieprz tributaries.