political ideas are regarded as "natural" or "secular", holding for a secular absolutism. The views on monarchical accountability espoused in his Dialogus (written between 1332 and 1347) greatly influenced the Conciliar movement and assisted in the emergence of liberal democratic ideologies. William argued for complete separation of spiritual rule and earthly rule. He thought that the pope and churchmen have no right or grounds at all for secular rule like having property, citing 2 Timothy 2:4. That belongs solely to earthly rulers, who may also accuse the pope of crimes, if need be. After the Fall God had given men, including non-Christians, two powers: private ownership and the right to set their rulers, who should serve the interest of the people, not some special interests. Thus he preceded Thomas Hobbes in formulating social contract theory along with earlier scholars. William of Ockham said that the Franciscans avoided both private and common ownership by using commodities, including food and clothes, without any rights, with mere , the ownership still belonging to the donor of the item or to the pope. Their opponents such as Pope John XXII wrote that use without any ownership cannot be justified: "It is impossible that an external deed could be just if the person has no right to do it." Thus the disputes on the heresy of Franciscans led William of Ockham and others to formulate some fundamentals of economic theory and the theory of ownership. Logic In logic, William of Ockham wrote down in words the formulae that would later be called De Morgan's laws, and he pondered ternary logic, that is, a logical system with three truth values; a concept that would be taken up again in the mathematical logic of the 19th and 20th centuries. His contributions to semantics, especially to the maturing theory of supposition, are still studied by logicians. William of Ockham was probably the first logician to treat empty terms in Aristotelian syllogistic effectively; he devised an empty term semantics that exactly fit the syllogistic. Specifically, an argument is valid according to William's semantics if and only if it is valid according to Prior Analytics. Theological thought Church authority William of Ockham denied papal infallibility and often went into conflict with the pope. However despite his conflicts with the papacy he did not renounce the Roman Catholic Church. Ockham also held that councils of the Church were fallible, he held