I don't think there /hasn't/ been a class based system in human prehistory even. Granted then the classes may have been hunter and gatherer. It is fundamentally

I don't think there /hasn't/ been a class based system in human prehistory even. Granted then the classes may have been hunter and gatherer. It is fundamentally inevitable as a result of specialization and even within the same the normal curve would effectively do the same. There are of course differences in the degrees of inequality.