if a system can be got rid of simply by us denying its existence (as could happen with a religious system, if we simply stopped believing in that particular god) then it clearly has no basis in a MATERIAL reality. That is to say, its purely an idealistic notion, not created by any kind of physical forces in the world.
If, as i believe, class is created by the material conditions of our society, then we cannot simply abolish it by denying it. We must tackle the social roots that caused it to come into existence in the first place. I think those roots lay in the lack of sufficient resources to adequately feed all the people in the world, or indeed within a particualr community, and so some was taken by the elite (originally the war and religious leaders) who have continued to do so, in various guises, ever since. Now, there are sufficient resources in the world for this not to be the case any more, it is a question of how the resources are distributed. Once some kind of equality has been achieved here, we can start talking about building a wonderful society where we are really all seen as equals (because we're not now, and its not just money, its power, its influence, its security, and safety, and a whole bunch of other stuff), but until then, i think its naive to think we are doing.