A standard reading in the history of economic thought sets the classical stream of economists drawing upon the influence of Adam Smith (Jean-Baptiste Say, David Ricardo, etc.) in opposition to a "black box" of social thinkers (Louis Blanc, Fourierism, Saint-Simonianism, Sismondi, Robert Owen). This article, however, argues that, in the first quarter of the 19th century, the Saint-Simonians and the liberal economist Jean-Baptiste Say can be seen to adopt convergent views during the famous controversy about commercial gluts. First, we show that the Saint-Simonians and Say both see undersupply and lack of industry as causes of gluts. Next, we assert that their intellectual affinities are also visible in their belief that increasing production remains an appropriate solution for gluts. Finally, this convergence is explained by their common belief in industrialism: Saint-Simonianism is embedded in a French industrialist tradition for which Say can be taken as representative. We argue that their common belief in industry explains their convergence.