DE MONARCHIA OF DANTE ALIGHIERI
CHAPTER XII: Christ in being born proved that the authority of the Roman Empire was just.
1. And especially those who call themselves zealots for the Christian faith  have "raged" and "imagined vain things" against Roman dominion; they have no pity for the poor of Christ,  but defraud them in the church revenues, even stealing their patrimony daily, and render the Church destitute;  pretending to Justice, they yet permit no executor of Justice to do his duty.
2. Nor is this impoverishment accomplished without the judgment of God, for the church revenues are neither given to relieve the poor whose patrimony they are, nor are held with gratitude to the Empire which bestowed them. Let them return whence they came. They came justly, they return unjustly, for though they were rightly given, they are wrongfully held.  What should be said of such shepherds? What, if with the depletion of the Church's substance the estates of relatives wax great?  Belike it were better to follow out the argument and await our Saviour's aid in pious silence.
3. I affirm, therefore, that if the Roman Empire did not come to be with Right, Christ in His birth authorized an injustice. This consequent is false; therefore the contradictory of the antecedent is true, since contradictory propositions are of such a nature that the falseness of a statement argues for the truth of its opposite. 
4. The falsity of this consequent need not be proved to those of the faith; for he who is of the faith will concede its falsity; if he does not do so, he is not of the faith; and if he is not of the faith, this argument concerns him not.
5. I demonstrate the consequent  thus: Whoever of his own free will fulfills an edict urges its justice by so doing; and since deeds are more persuasive than words, as the Philosopher states in his last book to Nicomachus, he is more convincing than if his approbation were verbal.  Now Christ willed to be born of a Virgin Mother under an edict of Roman authority, according to the testimony of Luke,  his scribe, in order that the Son of Man, made man, might be numbered as a man in that unique census. This fulfilled the edict. It were perhaps more reverent to believe that the Divine Will caused the edict to go forth through Caesar, in order that God might number Himself among the society of mortals who had so many ages awaited His coming. 
6. So Christ in His action established as just the edict of Augustus, exerciser of Roman authority. Since to decree justly presupposes jurisdictional power, whoever confirms the justice of an edict confirms also the jurisdictional power whence it issued. Did this power not exist by Right, it would be unjust.
7. And observe that the argument employed to disprove the consequent, though it holds to a certain degree, nevertheless, if reduced,  shows its force in the second figure,  just as the argument based on the assumption of the antecedent shows its force in the first figure. The reduction is made as follows: Every unjust thing is established unjustly; Christ established nothing unjustly; therefore Christ established no unjust thing. And thus by the assumption of the antecedent: Every unjust thing is established unjustly; Christ established an unjust thing; therefore Christ established things unjustly.
1. Witte points out that these same men are referred to in Purg. 6. 91: "Ah, folk that ought to have been at prayer, and to let Caesar sit in the saddle." They are the clergy who wrongly wish a controlling hand in the world of temporal things. In this chapter Dante is again making use of the language of Ps. 2. 1, and calling attention once more to the opening argument of Book 2.
2. Conv. 4. 27. 4: "Those which do belong to your profession ... take a tenth part and give it to God, that is, to those miserable ones to whom Divine favor alone remains."
Par. 12. 93: "Not the tithes which belong to God's poor."
Par. 22. 82: "Whatsoever the Church guards belongs all to the folk who ask in God's name." Cf. De Mon. 3. 10. 6.
3. Cupidity in the Church, as in men's minds (De Mon. 1. 11. 5), was the source and root of evil. Inf. 1. 49 uses as the figure of Avarice, or the Church grasping for temporal domain, a "she-wolf, that with all ravenings looked fraught in its leanness, and has already made much people wretched."
4. The donation of Constantine is meant. See De Mon. 3. 10. Par. 20. 56, the eagle speaks of Constantine's gift as "a good intention which bare ill fruit."
5. This was more true of Boniface VIII than of any other Pope, for he furthered the interests of his family and friends by all means in his power. Milman says of him in his Latin Christianity, Bk. 11, ch. 7: "Of all the Roman Pontiffs, Boniface left the darkest name for craft, arrogance, ambition, even for avarice and cruelty."
6. Par. 6. 21: "All contradictories are both false and true." That is, one is false and the other true, for contradictories are pairs of propositions so related to each other that both cannot be false. Wicksteed further explains that "They are of the form either of 'All A is B' and 'Some A is not B,' or 'No A is B' and 'Some A is B.' These four terms were usually arranged at the corners of a square in the logic books.
The contradictories are at opposite ends of the diameters, the source of the phrase "diametrically opposed.'"
7. That is, "Christ in his birth authorized an injustice."
8. Eth. 10. 1. 3. Cf. De Mon. 1. 13. 1. So also Thomas Aquinas says, "Concerning human actions and passions words are to be trusted less than deeds."
9. Luke 2. 1.
10. Purg. 10. 34: "The angel that came on earth with the decree of the many years wept-for peace ... opened heaven from its long interdict."
Par. 26 contains the computation of time from the fall to the redemption. Cf. 1. 118: "From that place whence thy Lady moved Virgil, for four thousand three hundred and two revolutions of the sun did I long for this assembly, and I saw him return to all the stars of his road nine hundred and thirty times whiles that I was upon earth." According to this, Adam makes the number of years 5232 from creation to crucifixion.
11. That is, to a syllogism.
12. The second figure has the middle term for predicate in both premises.