First Rule: People will believe a lie because they want it to be true or because they're afraid it might be true.
People are stupid; given proper motivation, almost anyone will believe almost anything. Because people are stupid, they will believe a lie because they want to believe it's true, or because they are afraid it might be true.
Second Rule:
The greatest harm can result from the best intentions.
Third Rule:
Passion rules reason.
Fourth Rule:
There is magic in sincere forgiveness, the magic to heal. In forgiveness you grant, but more so, in forgiveness you receive.
Fifth Rule:
Mind what people do, not only what they say, for deeds will betray a lie.
Sixth Rule:
Let reason be your only sovereign.
Seventh Rule:
Life is the future, not the past.
Eighth Rule:
Deserve victory.
Ninth Rule:
A contradiction cannot exist in reality. Not in part, nor in whole.
Tenth Rule:
Willfully turning aside from the truth is treason to one's self.
Rule Unwritten:
The rule of all rules. The rule unwritten. The rule unspoken since the dawn of history... But Barracus wanted you to know that it's the secret to using a war wizard's power. The only way to express it, to make sure that you would grasp what he was intending to tell you, was to give you a book unwritten to signify the rule unwritten.