“There are few writers or thinkers in history whose every word and grunt has been examined by hostile critics so minutely as Marx’s has”. Hal Draper.
The usual reference Marxists give those asking about “historical materialism” (aka the “materialist conception of history”) is Marx’s 1859 Preface to A Contribution to the Critique of Political Economy (example 1, example 2). If readers downloaded and printed it from the Marxists Internet Archive, depending on their printer settings, they’d get something like this:
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