DE MONARCHIA OF DANTE ALIGHIERI
CHAPTER VI: The order which is found in the parts of the human race should be found in the race as a whole.
1. As the part is related to the whole,  so is the partial order related to the total order. The relation of the part to the whole is as to its end and supreme good, and so the relation of the partial order to the total order is as to its end and supreme good.  We see from this that the excellence of partial order does not exceed the excellence of total order, but rather the converse. A dual order is therefore discernible in the world, namely, the order of parts among themselves, and the order of parts with reference to a third entity which is not a part. For example, in the army there is an order among its divisions, and an order of the whole with reference to the general. The order of the parts with reference to the third entity is superior, for partial order has its end in total order, and exists for the latter's sake. Wherefore, if the form of the order is discernible in the parts of the human aggregate, it should, by virtue of the previous syllogism, be much more discernible in the aggregate or totality, because total order or form of order is superior. Now, as is sufficiently manifest from what was said in the preceding chapter, it is discernible in all the units of the human race, and therefore must be or ought to be discernible in the totality itself. And so all parts which we have designated as included in kingdoms, and kingdoms themselves, should be ordered with reference to one Prince or Principality, that is, to one Monarch or Monarchy. 
1. Conv. 4. 29. 5: "Every whole is made up of its parts, ... and what is said of a part, in the same way may be said of a whole."
2. Par. 1. 103: "All things whatsoever have an order among themselves; and this is form, which makes the universe in the likeness of God. Here the created beings on high see the traces of eternal goodness, which is the end whereunto the rule aforesaid has been made."
Par. 10. 3: "The first and unspeakable Goodness made all that revolves in mind or in place with such order that he who observes this cannot be without tasting of Him."
Par. 29. 31: "Order and structure were concrete in the substances."
Cf: De Mon. 2. 7. 1, and note 3.
S. T. 1. 47. 3: "Ipse ordo in rebus sic a Deo creatis existens unitatem mundi manifestat. Mundus enim iste unus dicitur unitate ordinis, secundum quod quaedam ad alia ordinantur. Quaecumque autem sunt a Deo, ordinem habent ad invicem et ad ipsum Deum."
3. Conv. 4. 4. 1: "The whole earth mould be under one prince, who ... would keep the kings content within the limits of their kingdoms, so that peace should abide among them. wherein the cities should repose, and in this repose the neighbors should love one another, and in this love the families should supply all their wants; which done, man lives happily; for which end he was born."
Conv. 4. 4. 2: "And this office, for reason of its excellence, is called Empire, without any qualification, because it is the government of all governments. And so he who holds the office is called emperor, because he is a law to all and must be obeyed by all, and all others take their force and authority from him.. And thus it is evident that the imperial majesty and authority is the highest in human society."