Marx-Engels Correspondence 1879
Source: Karl Marx and Frederick Engels, Selected Correspondence (Progress Publishers, Moscow, 1975). Scanned and prepared for the Marxist Internet Archive by Paul Flewers.
... There is no room for us in a paper in which it is possible virtually to bewail the Revolution of 1848 that for the first time opened wide the portals to Social-Democracy. It plainly appears from this article  and Höchberg’s  letter that the stellar trio claims the right to set forth in the Sozialdemokrat, alongside the proletarian views, its own petty-bourgeois socialist views first clearly enunciated in the Jahrbuch. And I fail to see how you in Leipzig can prevent this without a formal breach, once things have come to such a pass. You continue to regard these people as Party comrades. We cannot do so. The article in the Jahrbuch draws a sharp and absolutely distinct line between us. We cannot even negotiate with these people so long as they assert that they belong to the same party as we. The points in question are points that can no longer be discussed in any proletarian party. To make them a subject of discussion within the party would be to put in question the whole of proletarian socialism.
As a matter of fact it is better that under these circumstances we do not cooperate. We should have had to protest constantly and to announce publicly our withdrawal after a few weeks, which after all would not have helped matters.
We greatly regret that just at this time of suppression we are unable to support you unconditionally. As long as the Party in Germany remained true to its proletarian character we set aside all other considerations. But now, when the petty-bourgeois elements that have been admitted openly show their true colours, the situation has changed. Once they are permitted to smuggle their petty-bourgeois ideas piecemeal into the organ of the German Party, this fact simply closes that organ to us...
As for the rest, world history is taking its course, regardless of these wise and moderate philistines. In Russia matters must come to a head in a few months from now. Either absolutism is overthrown and then, after the downfall of the great reserve of reaction, a different atmosphere will at once pervade Europe. Or a European war will break out which will also bury the present German Party beneath the inevitable struggle of each people for its national existence. Such a war would be the greatest misfortune for us; it might set the movement back twenty years. But the new party that would ultimately have to emerge anyhow would in all European countries be free from a mass of objectionable and petty matters that now everywhere hamper the movement.
Yours in friendship
1. This refers to an article under the title ‘Ruckblicke auf die sozialistische Bewegung in Deutschland’ (’the Socialist Movement in Germany in Retrospect’) written by Karl Höchberg, Eduard Bernstein and Karl Schramm and published in the Jahrbuch für Sozialwissenschaft und Sozialpolitik. See Marx and Engels, Circular Letter to August Bebel, Wilhelm Liebknecht, Wilhelm Bracke and others, September 1879 – Progress Publishers.
2. Karl Höchberg (1853-1885) – German social reformist, son of a wealthy merchant, in 1876 joined Social-Democratic Party, founded and financed a number of reformist newspapers and journals – Progress Publishers.