Historiographical position and political stance
He was a historian whose economic ideas passed through different phases. The acceptance of free trade principles in De la richesse commerciale was abandoned in favour of a critical posture towards free trade and industrialisation. Nouveaux principes d'économie politique attacked wealth accumulation both as an end in itself, and for its detrimental effect on the poor. He indicated contradictions of capitalism. He criticized the harsh conditions endured by the workers from the standpoint of a liberal republican.Sismondi is also regarded as an important early critic of economic inequality and social instability created by unchecked markets. He argued that national wealth should be measured by improvements in human welfare rather than production alone, because rising output could still leave workers in poverty or insecurity. He warned that industrial competition could create unemployment, overproduction, and unequal distribution of income when economic activity was left without restraint. Later historians of economic thought have described these arguments as an early foundation for welfare economics and broader critiques of capitalism, especially because Sismondi emphasized that economies should serve people rather than treat labor only as a cost of production. He was also a passionate opponent of slavery. Adolphe Blanqui said of him: "No writer has shown a sympathy more notable and more touching for the working classes." Jean-Baptiste Say referred to Sismondi as "that enlightened author, ingenious, eloquent and selfless".
His critique was noticed by Malthus, David Ricardo and J. S. Mill, who called his writing "sprightly, and frequently eloquent". While a young man at Edinburgh, Thomas Carlyle translated Sismondi's article on "Political Economy" for David Brewster's Edinburgh Encyclopædia. Sismondi subsequently influenced Carlyle's conception of the Dismal Science. Sismondi's Italian histories were read and esteemed by Lord Byron, Percy Bysshe Shelley, and Stendhal.
Sismondi influenced many major socialist thinkers including Karl Marx, Rosa Luxemburg, and Robert Owen. Marx thought Sismondi embodied the critique of the "bourgeois science of economics". In his notes, Marx excerpted various aspects of his analysis. Marx was particularly fond of Sismondi's statement that "The Roman proletariat lived almost exclusively at the expense of society. One could almost say that modern society lives at the expense of the proletariat, from the share which it deducts from the reward of his labor." Henryk Grossman argued that Sismondi was a significant methodological and theoretical predecessor of Marx, particularly by identifying the contradiction between use-value and exchange-value as fundamental to capitalism. In 1897, Vladimir Lenin wrote an article refuting Sismondi's work. Lenin said,
The contributor to Russkoye Bogatstvo states at the very outset that no writer has been "so wrongly appraised" as Sismondi, who, he alleges, has been "unjustly" represented, now as a reactionary, then as a utopian. The very opposite is true. Precisely this appraisal of Sismondi is quite correct.
In 1913, Rosa Luxemburg wrote a critique of Sismondi in The Accumulation of Capital.
The historian Jerzy Jedlicki writes:
All sorts of labels were pinned on this humanist from Geneva who lived in the period of the beginnings of industrial capitalism: he was regarded as a reactionary and a radical, a petty-bourgeois socialist and a romanticist. But when we read his work a hundred and fifty years later, we discover in him a precursor of the democratized, corrective liberalism of the twentieth century and also, in spite of all the defects of his economic theory, a precursor of concepts for the development of overpopulated countries with a low national income. Sismondi’s thought, unfettered by doctrine, has stood the test of time, something which cannot be said of many of his contemporaries.
