Class has a sense of humor. It knows that a good laugh is the best lubricant for oiling the machinery of human relations. Class never makes excuses. It takes its lumps and learns from past mistakes. Class bespeaks an aristocracy unrelated to ancestors or money. Some extremely wealthy people have no class at all, while others who are struggling to make ends meet are loaded with it. Class is real. You can't fake it. Class never tries to build itself up by tearing others down. Class is already up and need not attempt to look better by making others look worse. Everyone is comfortable with the person who has class because he is comfortable with himself. If you have class, you've got it made. If you don't have class, no matter what else you have, it won't make up for it.
There is a theory of societal evolution that goes like this: Barbarians invent a new culture. A middle class emerges to manage and help perpetuate the culture. An aristocracy eventually develops out of the middle class and devotes their energies to making things comfortable for themselves. Finally, a new set of barbarians smash everything apart and destroy the status quo so that the process must start all over again.