Thumbnail is Marx's manuscript for The German Ideology. Summary below is a compilation of my notes I wrote when reading Materialism and the Dialectical Method by Maurice Cornforth, along with general knowledge from reading various Marxist authors.
Often times, Marxists use the term "material conditions," and "dialectics." What does this mean? Why do Marxists care so much about material conditions? The answer is that Marxists seek materialist explanations for observed processes as opposed to idealist, and do so dialectically, as opposed to metaphysically. In other words, Marxists apply dialectical analysis to find materialist explanations for phenomena. Dialectical materialism is the world outlook of the proletariat as a class, and serves as the most vital ideological tool for overthrowing capitalism.
In order to understand dialectical materialism, we need to understand its component parts, materialism and dialectics, and their historical predecessors, idealism and metaphysics.
Idealism

Idealism is, in short, to put ideas prior to matter. Idealism has been used by feudal lords to justify their position above the serfs, forming the ideological basis for feudalism. The 3 major assertions of idealism are as follows:
-
Idealism asserts that the material world is dependent on the spiritual
-
Idealism asserts that spirit, or mind, or idea, can and does exist in separation from matter. (The most extreme form of this assertion is subjective idealism, which asserts that matter does not exist at all but is pure illusion.)
-
Idealism asserts that there exists a realm of the mysterious and unknowable, "above," or "beyond," or "behind" what can be ascertained and known by perception, experience, and science.
Early Materialism

Common idealist arguments are appealing to a supernatural "human nature," or "good vs. evil" explanations for processes. Materialism arose over time, as people grew to understand the world more deeply, and especially as a tool to overthrow the feudal aristocracy that justified its existence via the church. In other words, materialism rose to help the bourgeoisie. The 3 basic teachings of materialism as counterposed to idealism are:
-
Materialism teaches that the world is by its very nature material, that everything which exists comes into being on the basis of material causes, arises and develops in accordance with the laws of motion of matter.
-
Materialism teaches that matter is objective reality existing outside and independent of the mind; and that far from the mental existing in separation from the material, everything mental or spiritual is a product of material processes.
-
Materialism teaches that the world and its laws are fully knowable, and that while much may not be known there is nothing which is by nature unknowable.
Shortcomings of Metaphysical Materialism

The type of materialism that overthrew the feudal lords was still underdeveloped, and metaphysical. The bourgeoisie needed an explanation for why the feudal lords were illegitimate, but still needed to support their own static, permanent rule. This was called mechanistic materialism, for the bourgeois scientists saw the world as a grand machine repeating simple motions forever. Mechanistic materialism, therefore, makes certain dogmatic assumptions:
-
That the world consists of permanent and stable things or particles, with definite, fixed properties;
-
That the particles of matter are by nature inert and no change ever happens except by the action of some external cause;
-
That all motion, all change can be reduced to the mechanical interaction of the separate particles of matter;
-
That each particle has its own fixed nature independent of everything else, and that the relationships between separate things are merely external relationships.
Moving from Metaphysics to Dialectics

This, of course, has proven false. History did not end with the dissolution of the USSR, despite what modern mechanistic materialists claim. Mechanistic materialism relies on metaphysics, seeing everything as a static abstraction, devoid of its context. It has no explanation for how new qualities emerge, and ultimately fell to idealism to explain the "first mover," ie "God." Dialectical materialism holds instead:
-
The world is not a complex of things but of processes;
-
That matter is inseperable from motion;
-
That the motion of matter comprehends an infinite diversity of forms which arise one from another and pass into one another;
-
That things exist not as separate individual units but in essential relation and interconnection.
Dialectical Materialism

This became remarkable for the proletariat, as it sees nothing as static, and therefore marks the eventual downfall of the bourgeoisie. Putting it all together, we get the following:
- Dialectical materialism understands the world, not as a complex of ready-made things, but as a complex of processes, in which all things go through an uninterrupted change of coming into being and passing away.
In other words, when analyzing events and contextualizing them, we must always viee them as a struggle between the rising and the falling, the old and the new, for example the concentration of capital in markets and the rise in socialize labor.

- Dialectical materialism considers that matter is always in motion, that motion is the mode of existence of matter, so that there can no more be matter without motion than motion without matter. Motion does not have to be impressed upon matter by some outside force, but above all it is necessary to look for the inner impulses of development, the self-motion, inherent in all processes.
In other words, all movement is a result of contradiction. Your foot presses on the Earth, and the Earth presses back on you.

- Dialectical materialism understands the motion of matter as comprehending all changes and processes in the universe, from mere changes of place right to thinking. It recognizes, therefore, the infinite diversity of the forms of motion of matter from the simple to the complex, from the lower to the higher.
In other words, dialectical materialism recognizes that development exists as a change of quantity into quality. Addition or subtraction gives way to qualitative change. A balloon is filled with air, until at a given point it pops due to pressure buildup. Water goes from liquid to gas at its boiling point, and back into liquid when cooling down to said point.

- Dialectical materialism considers that, in the manifold processes taking place in the universe, things come into being, change and pass out of being, not as separate individual units, but in essential relation and interconnection, so that they cannot be understood each separately and by itself but only in their relation and interconnection.
In other words, everything is connected, and must be analyzed in context to truly understand it. A worker isn't just an individual, but instead part of a social class of many workers. Wages are not something invented brand new every time, but instead are set by societal standards, controlled by the ruling capitalist class.

Conclusion
Karl Marx created dialectical materialism by turning Hegel's idealist dialectic into a materialist one. Then, he applied it to the progression of society, creating historical materialism. By analyzing social structures and progress as a dialectical process based in materialism, we can learn from history and analyze where it's going. This is scientific socialism in progress. Human thought is shaped by our social experience, forming class consciousness and ideology. How we produce and distribute determines our ways of thinking.
Socialism and communism also have their own contradictions as well, and just because we progress on to socialism does not mean we cannot fall back to capitalism. The dialectical materialist world outlook understands that nothing is static, and there is always new contradiction and new movement from that.
If you keep these in mind, you can do your own dialectical materialist analysis. Always seek explanations based on the material, not the ideal, and always do so by contextualizing the processes, analyzing their contradictions, the unity and struggle of opposing tendencies. Quantitative changes lead to qualitative development, and progresses as a result of the conflict or struggle of opposite tendencies. There's much more to dialectical materialism, but this should help serve as a simple overview!
Science is necessarily materialist, it proceeds from the basis that matter is real and that the supernatural does not exist. It doesn't do this because of "opinion," but because there is not a single shred of evidence of the supernatural. Insisting on the existence of something outside of the material merely because it cannot be empirically disproven is still not evidence of this existing.
As for me "not understanding idealism" and "not reading any philosophy whatsoever," both of these are false assumptions. I have engaged with Hegel, and not just through Marx, Engels, etc. but through the source material itself. The purpose of this post is to give an extremely simplified introduction to dialectical materialism, not to give an expansive and comprehensive summary of idealism. I spent a few paragraphs on idealism, if you think I am genuinely reducing the entirety of idealist philosophy into a few paragraphs then this is just naked bad-faith.
As for the existence of god, an Absolute, a being outside of physical limitations and transcending them, this is without any base whatsoever. Simply claiming that I would not accept proof does not excuse you from providing it for your arguments to land, all you've done is insult me while utterly failing to disprove materialism.
You do not have a correct notion of science. You just ignored what I said.
I feel like slamming my head against the wall. That isn’t what happened. I did not insist that things outside the material exist because this cannot be empirically disproven, I said that you cannot assert that nothing outside of the material exists because there is no way for you to prove this within your view of what constitutes proof.
I did not accuse you of “reducing the entirety of idealist philosophy into a few paragraphs,” I accused you of listing as general features of idealism things which are not generally the case for “idealist” philosophers.
These are not assumptions. Read my explanation.
The absolute cannot be outside of anything. Do you know what words mean? And the absolute is not a being, the absolute is being, and the fact of existence necessarily leads to the absolute. Read the Science of Logic.
And I have; you refused to read where I told you the arguments are when they cannot be condensed to a quickly typed up message, and refused to acknowledge the arguments I gave directly or otherwise misunderstood them while simultaneously accusing me of arguing in bad-faith based on that misunderstanding. You haven't made a single actual argument in this entire conversation.
This is essentially your own trap, though. You're falling into pure agnosticism with respect to something that has never been proven, and you're dodging the necessity of providing proof by saying I won't accept it. I can understand why you'd be frustrated given the task of proving idealism correct to a materialist in your hands, but that doesn't mean I'm going to throw you a bone.
I'm aware that you didn't literally make the definitive claim that the supernatural exists. I carried the argument to its logical conclusion, either there is proof of the supernatural or there isn't. Refusing to provide proof is not an excuse to not do so.
Go on, elaborate then. Is this another point that you just make without base? An open accusation and nothing to back it?
They are assumptions. Just because I have a different view of philosophy does not mean I haven't engaged with it, and just because it seems evident that you've spent a great deal of time studying idealism does not mean you are correct about it with respect to dialectical materialism. Same goes for our simultaneous conversation on the Law of Value.
The Absolute that the subjective Absolute works towards is necessarily outside of human development. The steam engine did not arise from the self-movement of the Absolute, it could not have existed in human brains until steam was understood, and could not have come into reality until the definite conditions for its existence appeared. Ideas are not in reality prior to matter, thus the assumption that ideas can be prior to matter place the objective absolute outside of human development as a sort of post-facto resolution. This is why Hegel ends up affirming god, as without god his line of logic is incomplete.
I understand what you believe as someone (at least in this conversation) taking the side of Hegel, but I am not just talking about Hegel, but idealism in general. This also involves Berkley and other forms of subjective idealism, as opposed to Hegel's objective idealism. Existence does not lead to the Absolute, Hegel is wrong. Material is prior to ideas.
My arguments are the post itself, you claimed to be critiquing specific points I've made in the comments and this post as well. Your original point is that I cannot known that the supernatural does not exist, I understand perfectly well what you're getting at. What this line of logic that you pose necessarily leads down is agnosticism and an inability to effectively understand the world around us. The more we interact with the world and understand it, the less ground idealism has to stand on as we gather more and more materialist understanding.
I'm also aware that not all idealism is purely concerned with the supernatural, but instead may place consciousness or ideas as prior to matter instead of literal ghosts and whatnot. Hegel, as you know, is from the German school of idealism which is more objective than Berkeley's subjective idealism.
As a side note, when I looked at your comment history to check your earlier arguments in this thread, I noticed that you started talking with PugJesus. I'm sorry for the frustration you'll feel, if you think talking to me is frustrating. PJ has absolutely no understanding of Marxism and is generally a social fascist.
The quote pulled from Critique of the Gotha Programme is directly talking about conditions contemporary to Marx, with no socialist states. It's really as simple as that, not an argument against the state in the hands of the proletariat, nor did PJ respond to your excerpts from Anti-Dühring or the Manifesto of the Communist Party. I know you already know this, I'm not informing you of this, just laughing a bit at it.