From where Marx sat, observing history unfold in the middle of the 19th century, the Communist uprising against Capitalism was the inevitable next stage of human history. Its inevitability was due to both what he believed were inherent inconsistencies within the social structure of Capitalism, as well as his theory of historical materialism.
Marx based this historical materialism on the idea that there exists a universal social hierarchy between a base and a superstructure. The base, representing the economic structure of society, defines the superstructure, which includes the entirety of human consciousness: all science, political structures, religion, philosophy, etc. Thus a society’s material mode of production will determine that society’s organization and development (Marx, Preface to A Contribution to the Critique of Political Economy, 1856). As Marx put it: “Men make their own history, but they do not make it as they please; they do not make it under self-selected circumstances, but under circumstances existing already, given and transmitted from the past” (Marx, chapter one of The Eighteenth Brumaire of Louis Bonaparte, 1852). Men make their own history, but only within the confines of their inherited mode of production. As described by a more recent Marxist:
What productive forces do is define the parameters of what is possible for human will within a particular historical context that is constantly being redefined by human action — within that context there is a dialectical relationship between freedom and necessity. The task of historians is to seek to understand that relationship.
While it is common practice for historians to form a hierarchy of causality when analyzing individual events and movements, in the Marxist theory of base and superstructure we have instead a universal hierarchy for all historical events and movements. Marx’s theory was that all historical events are first and foremost the product of class conflict, and that we transition to different stages of history when the superstructure outgrows its base.
However, there are some glaring problems with this approach to history. As argued by John Stuart Mill, it is empirically impossible to determine a primacy of causality for historical events. Claiming that one particular cause of a historical event was the contributing cause can only be done by comparing it to the causes of similar historical events. Identifying the key variable empirically is thus a matter of subjective perspective, determined only by the range of comparisons. Mill wrote:
Plurality of Causes exists in almost boundless excess, and effects are, for the most part, inextricably interwoven with one another. To add to the embarrassment, most of the inquiries in political science relate to the production of effects of a most comprehensive description, such as the public wealth, public security, public morality, and the like: results liable to be affected directly or indirectly either in plus or in minus by nearly every fact which exists, or event which occurs, in human society. The vulgar notion, that the safe methods on political subjects are those of Baconian induction—that the true guide is not general reasoning, but specific experience—will one day be quoted as among the most unequivocal marks of a low state of the speculative faculties in any age in which it is accredited. Nothing can be more ludicrous than the sort of parodies on experimental reasoning which one is accustomed to meet with, not in popular discussion only, but in grave treatises, when the affairs of nations are the theme. (Mill, A System of Logic, 10.8 – p. 324)
Thus it’s ridiculous when Marxists make such historical claims as: “the reason there has been such a rapid succession of art movements from the nineteenth century onwards, when art in societies like ancient Egypt could persist unchanged for 3000 years, is the dynamic rate of change introduced by capitalist forces of production.” Regardless of whether or not such a statement is historically true, the claim is a sweeping generalization incapable of being proven.
However, this is not to argue for absolute positive skepticism. The fallacy of indiscriminate pluralism is merely the other ditch to historical reductionism. Rather, historical causes are indeed knowable and capable of factual verification, and historians are called upon to “carefully weigh one against the other in an integrated and refined interpretation” (David Hackett Fischer, Historians’ Fallacies, p. 176).
Recognizing this, even Marxists, despite their ideology, in practice have no problem using historical pluralism by counting any number of factors when explaining historical causality. As Engels wrote in a letter:
According to the materialist conception of history, the ultimately determining element in history is the production and reproduction of real life. Other than this neither Marx nor I have ever asserted. Hence if somebody twists this into saying that the economic element is the only determining one, he transforms that proposition into a meaningless, abstract, senseless phrase. The economic situation is the basis, but the various elements of the superstructure — political forms of the class struggle and its results, to wit: constitutions established by the victorious class after a successful battle, etc., juridical forms, and even the reflexes of all these actual struggles in the brains of the participants, political, juristic, philosophical theories, religious views and their further development into systems of dogmas — also exercise their influence upon the course of the historical struggles and in many cases preponderate in determining their form. There is an interaction of all these elements in which, amid all the endless host of accidents (that is, of things and events whose inner interconnection is so remote or so impossible of proof that we can regard it as non-existent, as negligible), the economic movement finally asserts itself as necessary. Otherwise the application of the theory to any period of history would be easier than the solution of a simple equation of the first degree. (Engels, Letter to Joseph Bloch, 1890)
And as Marx himself wrote: “the concrete is concrete because it is the concentration of many determinations, hence unity of the diverse” (Marx, ‘The Method of Political Economy’ from Grundrisse).
Thus Marxists continue to retain the theory of the primacy of class relations, while in practice holding to historical pluralism. This is why Marxist historians have managed to assimilate so well into mainstream historiography, because they’re not all that dissimilar in practice despite their reductionist theory. As David Hackett Fischer said “Good Marxists . . . . recognize this form of error and repudiate it, but as long as they hold to their various monisms, their explicit rejection of reduction is contradicted by the implicitly reductive nature of their interpretation” (David Hackett Fischer, Historians’ Fallacies, p. 174). And as Murray Rothbard wrote:
Twentieth century Marxists, from Lukacs to Genovese, have often tried to save the day from the embarrassment of the technological determinism of Marx and his immediate followers. They maintain that all sophisticated Marxists know that the causation is not unilinear, that the base and the superstructure really influence each other. Sometimes, they try to torture the data to claim that Marx himself took such a sophisticated position. Either way, they are characteristically obfuscating the fact that they have in reality abandoned Marxism. Marxism is monocausal technological determinism, along with all the rest of the fallacies we have depicted, or it is nothing, and it has demonstrated no inevitable or even likely dialectic mechanism. (Murray Rothbard, Classical Economics, p. 376)
Marxists need to turn to deductive reasoning because they cannot prove dialectical materialism through empirical observation. And shoehorning logical axioms based in natural phenomena upon human society is not obvious a priori. By claiming that the superstructure actively reflects the base, Marxists attempt to maintain human free will in an otherwise deterministic order. However, it still fails to explain why the mode of production must be the base, and the social order the superstructure, and not the other way around, something that cannot be done either deductively or inductively. It’s too bad Marx never attempted to provide us with any sort of logical theorem explaining the reasoning, because if he had he might have been forced to ditch Marxism.