Ruben’s “Marx and Materialism” is a pretty good book, but the author engages in a lot of bad-faith with other authors.

For instance, he criticizes Fisk for saying something like “practice determines truth”. Seeing as Ruben is willing to make a hundred distinctions, disambiguations to save Marx’s or his own writing, why can he not do the same with Fisk?

It is pretty obvious what Fisk is getting at when he makes such a statement, and indeed it is important since Fisk really tracks what is specific to a Marxist theory of knowledge ( besides activism, social realism etc.). He is not saying that ontologically, human thought or practice determines the existence, character and relations of the object, but that epistemically it is necessary to engage in practice – not pure contemplation- in order to identify the truth of a piece of purported knowledge. Hence, no apriori language by itself can guarantee the truth of such and such a piece of knowledge, no truth about the natural or social world can be deduced from some axiomatic ,but must be contingently discovered by a posteriori methods and languages that reflect the structure of reality. Practice e.g. an experiment- is the criterion- the test- of the objectivity of theory. This is a thought old and persistent in Marxism (look at Bukharin’s introductory address in “Sciences at the Crossroads”. Ruben goes against the whole tradition of the “union of theory and practice” in which practice is a final-criterion of objectivity, truth of knowledge.)

Fisk is making a statement about truth on the side of epistemology- what allows humans to identify the truth of their knowledge- while Ruben attacks him on the side of ontology, charging him with an anti-realist ontology vis-a-vis the truth i.e. that truth radically depends on human cognition and praxis . I don’t get this lack of generosity in interpreting others.

Overall, this is an excellent book. It is a strong representative of the interactions between Marxism and analytic philosophy.