Is Marx considered an important classical economist?

Question

In a post on the politics stack exchange, I came across the following description of how Marxism fits into the history of economic thought:

Most professional economists consider Marx' work on economic theory to be a substantial part of economic theory. Marx and Engels are included in the list of great classical economists, along with Adam Smith, Jeremy Bentham, David Ricardo, and Thomas Malthus. Marx pointed out that the long-term equilibrium for the "standard of living" is what a class insists upon before having, raising, and equipping enough children to replace itself. Several key concepts of economics (including "Cobb-Douglas production functions" and "value added") are designed to explain Marx' observations about the fraction of a factory's revenue that is not paid out for materials or proletarian labor.

The idea that "the long-term equilibrium for the 'standard of living' is what a class insists upon before having, raising, and equipping enough children to replace itself." seems foreign to me as an idea in economics and I am curious about the accuracy of the claims about Cobb Douglass and Value added, since they were not supported with references.

Is Marx commonly considered to be an influential classical economist, and if so, what is an example of an idea he added to economics as a discipline?

Answer 1

Among economic historians, Marx is often considered the most important economist of the 19th century. His attempts to provide a systematic explanation of the functioning of capitalism was on a far grander scale than anyone who preceded him, and in that sense, he reset the bar very high for what would henceforth be considered comprehensive economic theory, even if parts of it were fundamentally flawed. Refer to Mark Blaug's classic text Economic Theory in Retrospect (Chapter 7) for a nice attempt to parse out Marx's economic theory from the rest of his ideas. This is a standard and authoritative text in the history of economic theory.

Blaug says of Marx "Marx the economist is alive and relevant today in a way none of the writers we have thus far considered." Those considered were Smith, Malthus, Say, Ricardo, & Mill.

In terms of his understanding of the dynamic long run evolution of economic systems, the nature of technical change, business cycles, and volume of employment, his insights were often brilliant, transformative and unparalleled in any writers that preceded him, and remain deeply influential. (I'm paraphrasing Blaug here)

[It's worth mentioning that Blaug did his Ph.D at Columbian under George Stigler, who was a key leader in the Chicago School. So Blaug was hardly a lightweight, nor a "pinko" ;) ]

Answer 2

Marx is indeed an influential classical economist, however he added almost nothing to economics as a discipline. His theories of labor value, exploitation and modes of production were all articulated before him, which he acknowledged. What he did do was systematize and popularize these theories as scientific. Marx was closer to Malthus than to Smith in terms of his historical influence and present unpopularity.

Answer 3

There is a major disciplinary specification problem here: “who is an economist?”

At the time Marx was active as an author (including posthumously with Engels) the field of knowledge was known as “political economy,” so as to distinguish it from the domestic economy of household management—both from the Greek oikos. Political economy was, and still can, be distinguished as a scholarly discipline as the study of the formation of “value,” or the question of “what is something worth?” At the time three methods of dealing with this were present in the discipline: absolute labour content, proto-marginalisms, and utilitarianisms (subjective or moralistic evaluations).

Marx primarily engaged with political economy through a critique of the labour theory of value, positing instead a realised (ie sold), valorised (ie applied to production, not wasted) socially-necessary (technical organisation), labour power (skill organisation), averaged (exertion) theory of value with the price of buying actual living labour to convert to labour power politically determined by the balance of class conflict (that is, the price of labour may be below life time replacement or day to day replacement: starvation wages may be what the politics bear).

He also spent his time viciously heckling utilitarians over the incommensurability of internal desires and proto-marginalists.

Economics, as a discipline, is founded in the reaction to the incommensurability problem of subjective prices, and instead posits marginal differences in effective demand instead of human desires.

In the sense that Marx’s work is hard to reconcile as a system with marginalism, it is hard to posit Marx as an economist rather than a political economist. However, in the sense that Marx specifies a number of useful problems, represents the most highly developed outcome of labour theories of value, and that a whole load of scholars trained in Marx’s work work in economics departments he is of continuing influence in that discipline.