As presentes notas examinam o debate sobre a teoria marxiana do valor entre Werner Sombart e Friedrich Engels, por correspondência, motivado a partir do ensaio crítico de Sombart sobre o Livro 3 de O capital (1894), de Karl Marx, que foi organizado e editado por Engels. Nesse debate é possível identificar, tanto na réplica de Engels (o que o leva a escrever um apêndice ao Livro 3) quanto nos questionamentos de Sombart, a existência de um diálogo entre as perspectivas dos dois intelectuais sobre a teoria do valor de Marx. Assim, essas notas apresentam breves esboços biográficos de Sombart e Engels, contextualizam e comentam o debate teórico público e a correspondência entre ambos sobre a teoria econômica e social marxiana.
The present essay addresses a debate between Werner Sombart and Friedrich Engels, by correspondence, about a review written by Sombart at the time of the publication in 1894 of Book 3 of The Capital, organized and edited by Engels. It is possible to identify both in Engels’ concern with Sombart’s questions (which led him to write an appendix to Book 3), and in the development of Sombart’s studies (at least while his focus was on the subject of Socialism) from the suggestions of reading and understanding of Marxian categories that Engels made to him, the existence of a dialogue between the perspectives of two key intellectuals of social thought not only of that time, but of its own theoretical core. This article thus presents the biography of both authors, and comments on the correspondence between the two, adding Engels’ correspondence to third parties, commenting on Sombart, and presenting a reply to the questions of the then young economist and sociologist.