The Eight virtues form the basis of the primary philosophy of the Ultima CRPGs. Each virtue is associated with One of the eight largest cities, character classes, some combination of the three great principles: Truth, Love, and Courage, a rune, a colour, a mantra, a vice which is also the name of a dungeon near the city, and the anti-principles of it's principles. Acting in accordance with the virtues raises your karma while acting counter to them lowers your karma. The absolute value of your karma (amoung other things) determines your mana, if you have any magical ability to begin with. (sorry that most of the mantras are missing but as I remember them I'll add them)
Valour
Honesty
Justice
Honour
Sacrifice
Humility
Spirituality
In the character creation of some of the Ultimas your class was decided by
The Paradox of the Avatar. A series of situations is posed to the player by a
Gypsy, each requires a decision between two of the virtues, the principle or principles you favour are used to determine your primary virtue and class. (I normal favour truth and therfore become a mage).