"The Call," New York, February 27, 1910, deems "The Origin of the Family" worthy of editorial comment: "The one book that contains in small compass what every woman ought to know is Fredrick Engel's 'The Origin of the Family.' Every Socialist woman should become a book agent to sell this book."
"The International Socialist Review," October, 1902, expressed its admiration of Engel's work by stating that "this book has long been known as one of the great Socialist classics and has been translated into almost every other language than English.... The book is really one of the two or three great Socialist classics; and now that it is in English, it must find a place in the library of everyone who hopes to master the real fundamental philosophy underlying Socialism."
"The Origin of the Family," notwithstanding the fact that it contains matter too foul to comment on, for example a certain comparison that is made on page 39, was listed with the books sold at the National Office of the Socialist Party, and at Chas. H. Kerr and Company, the largest Socialist publishing company in the United States.
Ernest Untermann, the American Socialist who translated Engel's work into English, writes on page 7 of the preface of the 1907 edition: "The monogamic family, so far from being a divinely instituted union of souls, is seen to be the product of a series of material, and in the last analysis, of the most sordid motives."
Rives La Monte, in "Socialism Positive and Negative," tells his readers that "from the point of view of this Socialist materialism, the monogamous family, the present economic unit of society, ceases to be a divine institution, and becomes the historical product of certain definite economic conditions. In the judgment of such Socialists as Fredrick Engels and August Bebel, we shall probably remain monogamous, but monogamy will cease to be compulsorily permanent." ["Socialism, Positive and Negative," by Rives La Monte, page 98 of the 1907 edition.]