[Marxism] What is wrong with positivism?

[Pance Stojkovski]

checkout WikiPedia:
  http://en.wikipedia.org/wiki/Positivist
   
  esp. this point in relation to Marxism:
   
  "Orthodox Marxism and predictive dialectics are highly positivist systems of theory; however Marxism rejects positivism and views it as subjective idealism, because it limits itself only to facts and does not examine the underlying causes of things."
   
  Pance