The two sides of Marx: Hegelian and Communist Marx
"Theses on Feuerbach" is the tipping point between the young Marx, who was still heavily influenced by Hegel, and the "old" Marx, who is infamous for his theory of exploitation and class struggle. The works of Hegelian Marx were discovered long after Communist Marx became widely known.
The proletariat and the "universal" class
To understand Marx's obsession with the proletariat as a class, we have to go back to Hegel's "Philosophy of the Right," where he outlines the need for a "universal" class that acts on behalf of the common good instead of the various interests groups in society. For Hegel, the way to achieve the common good was to have a "universal" class of civil servants. In "On the Jewish Question," Marx agrees with Hegel on the need for a universal class that acts on the good of all. Still, he disagrees that the government, through its class of "universal" civil servants, is the right approach and instead points to the proletariat as the most suitable candidate for this class.
Philosophy of Praxis
"[philosophy of praxis is] the essence of Marxism, [where] the truth is not the subject reflecting on the object, but the interaction of the subject with the object."
Marx abandons the idea of alienation he laid out in his "Paris Manuscripts" because despite being a solid argument for why individuals were worse off in modernity, it did not push individuals to act on that knowledge. Thus Marx moved away from alienation and into historical materialism in his pursuit of developing the philosophy of Praxis, one that forces people to act to change their circumstances and help reunite the subject with the object. As discussed previously, Marx was a revolutionary looking for a revolution, and the philosophy of Praxis was a suitable medium to achieve that.
Two paths out of the alienation of the modern world: action (Praxis) and contemplation
The philosophy of Praxis, one focused on action, can be contrasted with the work of Hegel, who saw the way out of alienation as achievable only through the contemplation of the individual. For Marx, the philosophy of Praxis also symbolizes that change cannot happen in solitude but instead is best done by the collective.
Dialectic, or the world as constantly in motion
"No man ever steps in the same river twice. For it's not the same river and he's not the same man." - Heraclitus.
In "Theses on Feuerbach," Marx emphasizes dialectic, which symbolized that the world is in constant motion where "no man ever steps in the same river twice." The way to understand this particular definition of dialectic is by contrasting it with determinism, which sees the world as being bound in its ability to change dramatically.
Importance of materialism
"Tell me, you know, how much money you have in your pocket and I will tell you what your ideas are, to put it very simplistically."
For Marx, materialism becomes a big part of his philosophy because he acknowledges that individual reality is being derived from sensuous experience.
The lasting legacy of Marx's materialism
"Before Marx, you went into a museum and the museum was about great people. Right? These were kings and queens and generals and popes whose pictures were presented there, and this was the way how history was described. Now you go into a history, and now you can see this is a living room, how people lived in Roman times, and this is the way how they ate, this is the way how they cooked, and these are the instruments by which they produced the stuff what they cooked in their kitchen. This is how a modern historical museum looks like, and this comes–this is really a revolution from Marx. History is not the history of great ideas and great men, or great women. History is the idea of the actual way how people lived and produced and reproduced their ideas."
Modes of production as a driver for the evolution of societies