Read this: In theory at least, all Polish noblemen were social equals. Also in theory, they were legal peers. Those who held 'real power' dignities were more privileged but these dignities were not hereditary. Those who held honorary dignities were higher in 'ritual' hierarchy but these dignities were also granted for a lifetime. Some tenancies became hereditary and went with both privilege and titles. Nobles who were not direct barons of the Crown but held land from other lords were only peers "de iure".
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): Nobles held land form whom?
other lords were only peers "de iure"