This perfection the Philosopher means in the seventh chapter of Physics, when he says: "Each thing is especially perfect when it touches and joins its own proper or relative virtue; and then it is especially perfect according to its nature. It is, then, possible to call the circle perfect when it is truly a circle, that is, when it is joined with its own proper or relative virtue, it is then complete in its nature, and it may then be called a noble circle." This is when there is a point in it which is equally distant from the circumference. That circle which has the figure of an egg loses its virtue and it is not Noble, nor that circle which has the form of an almost full moon, because in that its nature is not perfect. And thus evidently it is possible to see that commonly, or in a general sense, this word Nobility, expresses in all things perfection of their nature, and this is that for which one seeks primarily in order to enter more clearly into the discussion of that part which it is intended to explain. Secondly, it remains to be seen how one must proceed in order to find the definition of Human Nobility to which the present argument leads. I say, then, that since in those things which are of one species, as are all men, it is not possible by essential first principles to define their highest perfection, it is necessary to know and to define that by their effects. Therefore one reads in the Gospel of St. Matthew, when Christ speaks, "Beware of false prophets: by their fruits ye shall know them." And in a direct way the definition we seek is to be seen by the fruits, which are the moral and intellectual virtues of which this Nobility is the seed, as in its definition will be fully evident. And these are those two things we must see before one can proceed to the others, as is said in the previous part of this chapter. CHAPTER XVII. Since those two things which it seemed needful to understand before the text could be proceeded with have been seen and understood, it now remains to proceed with the text and to explain it, and the text then begins: I say that from one root Each Virtue firstly springs, Virtue, I mean, that Happiness To man, by action, brings And I subjoin: This, as the Ethics teach, Is habit of right choice; placing the whole definition of the Moral Virtues as it is defined by the Philosopher in the second book of Ethics, in which two things principally are understood. One is, that each Virtue comes from one first principle or original cause; the other is, that by "Each Virtue" I mean the Moral Virtues, and this is evident from the words, "This, as the Ethics teach"