When asked whether or not we are Marxists, our position is the same as that of a physicist or a biologist when asked if he is a 'Newtonian', or if he is a 'Pasteurian'

via comrade Thoreau Redcrow 

"When asked whether or not we are Marxists, our position is the same as that of a physicist or a biologist when asked if he is a 'Newtonian', or if he is a 'Pasteurian'. There are truths so evident, so much a part of people's knowledge, that it is now useless to discuss them…The merit of Marx is that he suddenly produces a qualitative change in the history of social thought. He interprets history, understands its dynamic, predicts the future, but in addition to predicting it (which would satisfy his scientific obligation), he expresses a revolutionary concept: the world must not only be interpreted, it must be transformed. Man ceases to be the slave and tool of his environment and converts himself into the architect of his own destiny."
― Che Guevara,
'Notes for the Study of the Ideology of the Cuban Revolution', 1960
http://www.marxists.org/archive/guevara/1960/10/08.htm