Dialectical or historical materialism?

[Elysian]

Marxism is sometimes called dm, sometimes hm.

What's the difference, if any?

[hatzel]

The former applied to history becomes the latter.

[NGNM85]

No, but thanks for asking.

[La Comédie Noire]

Historical Materialism is the Dialectics of history as mentioned before. Though I wish to point out that everything said in HM can be rephrased non dialectically. Including the mutual influence of ideas and material reality.

[Ocean Seal]

Historical Materialism is easier to understand, albeit it is useful to think using the dialectic when attempting to understand the materialist conception of history. Overall I would find that at least at a basic level the dialectic is fairly useful.

[l'Enfermé]

Marxism is sometimes called dm, sometimes hm.

What's the difference, if any?
Marxism is never called that by any serious person. Some consider the two to be central to Marxism, though Marx never actually even used the term "dialectical materialism" or "historical materialism"...dialectical materialism is something more common in the works of Kautsky and Plekhanov and their disciple, Lenin, actually.

[Luís Henrique]

They are the same thing.

Luís Henrique

[Thug Lessons]

Historical materialism is fairly well-defined, and the earliest full description of it comes from the prefrace to Marx's Contribution to a Critique of Political Economy:


In the social production of their existence, men inevitably enter into definite relations, which are independent of their will, namely relations of production appropriate to a given stage in the development of their material forces of production. The totality of these relations of production constitutes the economic structure of society, the real foundation, on which arises a legal and political superstructure and to which correspond definite forms of social consciousness. The mode of production of material life conditions the general process of social, political and intellectual life. It is not the consciousness of men that determines their existence, but their social existence that determines their consciousness. At a certain stage of development, the material productive forces of society come into conflict with the existing relations of production or – this merely expresses the same thing in legal terms – with the property relations within the framework of which they have operated hitherto. From forms of development of the productive forces these relations turn into their fetters. Then begins an era of social revolution. The changes in the economic foundation lead sooner or later to the transformation of the whole immense superstructure.

In studying such transformations it is always necessary to distinguish between the material transformation of the economic conditions of production, which can be determined with the precision of natural science, and the legal, political, religious, artistic or philosophic – in short, ideological forms in which men become conscious of this conflict and fight it out. Just as one does not judge an individual by what he thinks about himself, so one cannot judge such a period of transformation by its consciousness, but, on the contrary, this consciousness must be explained from the contradictions of material life, from the conflict existing between the social forces of production and the relations of production. No social order is ever destroyed before all the productive forces for which it is sufficient have been developed, and new superior relations of production never replace older ones before the material conditions for their existence have matured within the framework of the old society.
http://www.marxists.org/archive/marx/works/1859/critique-pol-economy/preface.htm

This formulation was later repeated in Engels's Socialism: Utopian and Scientific, though many later Marxists, particularly the critical theorists of the Frankfurt School and their supporters, are critical of Engels's take and of the 'reductionist' understanding of historical materialism as well. I'm less critical myself, but in any case it's not an uncontroversial proposition in Marxism, let alone the left as a whole.


As for dialectic materialism, that's less clear, at least to me. Neither Marx not Engels ever used the term, let alone applied it to their own work. It was coined by other Marxists following Marx's death, and later taken up by the Soviet Union and promoted as the official state ideology. I don't really know that much about it beyond that.