(If you don't know what that means, either look it up or go back to the Romper Room.) Throughout all known human history, there have been multiple social classes in tribes, villages, and ultimately nations. More significantly, every social class has always had different aims and goals. Usually, those goals are not compatible with one another, and that's what leads to resentment, or classism. Nobody has proposed any sort of model by which different classes can "all just get along," so that leads me to an inescapable conclusion. If there were no classism, there would be no classes. (By the way, I'm not opposed to the concept of a classless society. Most Americans would probably be happier in one. Of course, we all know that every attempt in history to create a classless society has ended in failure.) So unless you plan to make a case for why "classism" is a legitimate concept, please don't use the word. It sounds about as silly as "evilphobia."