Esse quam videri - To be, rather than to seem
This state motto might as well get the prize for Classical authenticity. Without trying to come up with something unique and of questionable value, North Carolinians went straight to the source of nearly everything that is good in Latin prose: Cicero. Right? Actually, the phrase is a little bit out of context: Virtute enim ipsa non tam multi praediti esse quam videri volunt ("De amicitia", 98). Cicero does not speak of being per se, he speaks about being endowed with virtue. If you are have left is "esse quam videri" it becomes rather unclear: to be what? to seem to be what?
A lesser known author, Sallust uses this phrase in his book on the Catilinarian war: Esse quam videri bonus malebat (Cat. 54). Sallust was speaking about Cato, not Catiline, of course.
Regardless, a good motto. North Carolina spent a long time coming up with it, being the only one of the original 13 states without an official motto all the way until 1893!
It remains to be added that dozens of other organizations, mostly private schools, use Esse quam videri as their motto. Most significant use of a similar phrase is by Brepols Publishers. Their older publications displayed this motto: Melius esse quam videri. The phrase is also found in some family mottos, such as the Thurstons of Hoxne Abbey in Suffolk and the Robbins family in Somersetshire.