in 1736 jordan became the crown prince's literary secretary, in 1740 he was appointed curator of the universities, and in 1744 vice president of the prussian academy of sciences. at the rheinsberg castle he was the member of a radical intellectual circle including general heinrich august de la motte fouqué. jordan was an avid collector of banned radical and "socinian" books, obtaining copies of the "meditationes" of theodor ludwig lau, jean bodin's "colloque", and adrian beverland's "état de l'homme" for his personal library.