I am not a Marxist and he wrote some questionable stuff, but one of his core messages is one that most libertarians and anarchists acknowledge as well, I believe
The Alienation of Production (Entfremdung der Arbeit)
The concept basically says that in our modern age the worker does not own nor does he really know the final product that he is working for.
Translated from German wikipedia
Die Entfremdung durch das Lohnarbeitsverhältnis zwischen Arbeiter und Kapitalist manifestiere sich in vier Formen
The alienation through the Wage-employment-relation between Worker and Capitalist manifests in four forms:
1 Dem Arbeiter tritt sein Arbeitsprodukt als fremdes Wesen und unabhängige Macht gegenüber. Sein Arbeitsprodukt gehört nicht ihm, sondern einem Anderen.
1 The worker encounters his product as a foreigner/stranger and independent power. He does not own his product, it belongs to someone else.
2 Die eigene Tätigkeit ist eine fremde, dem Arbeiter nicht angehörige Tätigkeit. Die Arbeitstätigkeit befriedigt keine Bedürfnisse des Arbeiters, sie dient nur als Mittel, um Bedürfnisse außer ihr zu befriedigen, so dass die Arbeit als eine Pest geflohen wird, sofern kein materieller Zwang herrscht. Die Äußerlichkeit der Arbeit zeige sich darin, dass die Arbeitsverausgabung dem Arbeiter nicht eigen ist, sondern einem anderen gehört.
2 The own work is a foreign one, that is not a part of the worker. The work does not satisfy any need/urge of the worker, it is a tool to satisfy the needs besides it, so that the work becomes a plague and is fled as soon as there is no material(monetary) need. The appearence of work manifests in work-expenses that are not owned by the worker but by someone else.
3 Sowohl der "Gattungscharakter" des Menschen, die freie und bewusste Tätigkeit, wie sein Gattungsleben, die Bearbeitung der Umwelt und der Gesellschaft, sind dem Arbeiter nicht möglich, sein "Gattungswesen" ist ihm entfremdet.
3 The "species character" of the human, the free and concious work, and his public life, the processing and reworking of environment and society, are not possible for the worker since his "species class" is foreign to him.
Species character and species class are actually quite unique concepts used by Marx. I used the word "public life" to translate "Gattungsleben" and maybe "public" would make more sense than the official and literal translation "species". It is a way of describing the thoughts and values of a collective. I would guess a lot of the left wing Collectivism is based on this. Covering Collectivism vs Individualism is quite a topic, that I will not cover here, but maybe in a separate post some day.
4 Eine unmittelbare Konsequenz aus der Entfremdung von Arbeitsprodukt, Tätigkeit und dem menschlichen Wesen ist die Entfremdung des Menschen von dem Menschen.
4 A direct consequence of the alienation of the workproducts, the occupation/work and the human nature is the alienation of humans form other humans.
The german quotes are taken from https://de.wikipedia.org/wiki/Entfremdete_Arbeit , translation was done by me
My Opinion
Reading up on Marx I remember how hard to read he is even for a native German. In hindsight that is actually a huge minus that I have have to give to Karl Marx, a self proclaimed ambassador of the more uneducated working class.
There is also a lot lost in translation. The word "fremd" means "foreign/unknown/strange/alien" at the same time so "Entfremdung" is already tough to translate.
Despite that I have to say I agree with the points Marx made, even about Collectivism. The solution to get rid of private property is delusional – no doubt, but the problems Marx described are very real in my opinion.
As someone who knows some Marx and many other German political and specifically left-wing literature (school FORCED me to read it ;), I do see the meaning in the phenomenons described by Marx. But instead of explaining the concepts more detailed to an unknown audience I would like you to comment with your question and criticism below.
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