The marxist theory although a bit wide and comprehensive in scope is quite vague and somehow unrealistic. It lacks consistency and its almost not practicable in the real world. Take for instance its postulation that socialism can only be achieved by class conflicts and over the years that margin is been widened and capitalism still retained its standing even when karl's theory predicts its end to another state phase. But generally karl marx theory have been of help in helping understand the political, economic and social strata of the society overtime.