Opus Nonaginta Dierum

Ockham's theological and political treatise on the Franciscan poverty controversy — arguing against papal authority over secular rulers and for the legitimacy of Franciscan poverty.

The poverty controversy: Ockham argues that the Franciscan right to use goods without owning them is theologically defensible — a detailed critique of Pope John XXII's condemnation. The broader argument: papal authority is limited by natural law and reason — the Pope cannot command what is contrary to Scripture or natural reason. One of the founding texts of political anti-papalism.