Dante inquires into three questions concerning monarchy:
1. Whether universal monarchy is necessary to the well-being of the world
2. Whether the Roman people took on Empire by right
3. Whether imperial authority comes from God directly or the Pope
Papal vs. Imperial Authority
1. The Priest and King Argument
Argument for Papal Authority: From the text of the first book of Kings, they take the creation and deposition of Saul, and say that King Saul was placed on the throne and removed from it by Samuel, who was acting as God’s vicar by His command. Just as he, as God’s vicar, had the authority to give and take away temporal power and transfer it to someone else, so now too God’s vicar, the head of the universal church, has the authority to give and to take away and even to transfer the sceptre of temporal power; from which it follows that imperial authority is dependent on papal authority.
Refutation: Samuel acted on that occasion not as vicar but as a special emissary for a particular purpose, that is to say as a messenger bearing God’s express command: this is clear because he did and reported only what God told him to. It is one thing to be a vicar, and quite another to be a messenger or minister; just as it is one thing to be a writer and another to be an interpreter. For a vicar is a person to whom jurisdiction is entrusted within the terms of the law or at his own discretion; and thus within the limits of the jurisdiction entrusted to him he can take action by applying the law or using his own discretion in matters of which his lord knows nothing. But a messenger qua messenger cannot do this, who is entirely dependent on the will of the person who sends him.
2. The Perfect Man Argument
Argument for Papal Authority: Adopting a principle from the tenth book of the Metaphysics, they say: all things belonging to a single species are referred to one thing which is the measure for all things which belong to that species. All men belong to the same species, therefore they are to be referred to one man as their common measure, the perfect man, and the model of what is most unified in his species, as we can deduce from the end of the Ethics.
Since the supreme Pontiff and the Emperor are men, it must be possible to refer them to a single man. And since the Pope must not be referred to any other man, it remains that the Emperor along with all other men must be referred to him, as to their measure and rule.
Refutation: Pope and Emperor are what they are by virtue of certain relationships, i.e. by virtue of Papal and Imperial office, which are respectively relationships of “paternity” and of “lordship”, it is clear that Pope and Emperor must be assigned as Pope and Emperor to the category of relationship, and as a consequence be referred to something within that category. There is one measure to which they are to be referred as men, and another as Pope and Emperor.
Insofar as they are terms which express a relationship, they are either to be referred one to the other, or else to some third entity to which they are to be referred as to a common unity. And this will either be God himself, in whom all principles form an absolute unity, or else some entity lower than God, in which the principle of authority, derived from the absolute principle and differentiating itself from it, becomes distinctive and individual.