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”

Hence it is to be known that our most right and proper fruits are the Moral Virtues, since on every side they are in our power; and these are differently distinguished and enumerated by different philosophers.  But it seems to me right to omit the opinion of other men in that part where the divine opinion of Aristotle is stated by word of mouth, and therefore, wishing to describe what those Moral Virtues are, I will pass on, briefly discoursing of them according to his opinion.

There are eleven Virtues named by the said Philosopher.  The first is called Courage, which is sword and bridle to moderate our boldness and timidity in things which are the ruin of our life.  The second is Temperance, which is the law and bridle of our gluttony and of our undue abstinence in those things requisite for the preservation of our life.  The third is Liberality, which is the moderator of our giving and of our receiving things temporal.  The fourth is Magnificence, which is the moderator of great expenditures, making and supporting those within certain limits.  The fifth is Magnanimity, which is the moderator and acquirer of great honours and fame.  The sixth is the Love of Honour, which is the moderator and regulator to us of the honours of this World.  The seventh is Mildness, which moderates our anger and our excessive or undue patience against our external misfortunes.  The eighth is Affability, which makes us live on good terms with other men.  The ninth is called Truth, which makes us moderate in boasting ourselves over and above what we are, and in depreciating ourselves below what we are in our speech.  The tenth is called Eutrapelia, pleasantness of intercourse, which makes us moderate in joys or pleasures, causing us to use them in due measure.  The eleventh is Justice, which teaches us to love and to act with uprightness in all things.

And each of these Virtues has two collateral enemies, that is to say, vices; one in excess and one in defect.  And these Moral Virtues are the centres or middle stations between them, and those Virtues all spring from one root or principle, that is to say, from the habit of our own good choice.  Wherefore, in a general sense, it is possible to say of all, that they are a habit of choice standing firm in due moderation; and these are those which make a man happy in their active operation, as the Philosopher says in the first book of the Ethics when he defines Happiness, saying that Happiness is virtuous action in a perfect life.