I made up my mind, as I told everybody here, to play a trick on Bismarck and write something (Morgan)  that he simply could not prohibit. But it won t work, in spite of all my efforts. I simply cannot word the chapter  on monogamy and the concluding chapter on private property as a source of class antagonisms and also as a lever for the disintegration of the ancient community system in a way to get them through under the Anti-Socialist Law. Let the devil take me, I can do no other, as Luther said. There would be no point in writing it if I merely wanted to give an objective report on Morgan without treating him critically, without utilising the new results and presenting them in connection with our views and the conclusions already reached. Our workers would gain nothing by this. Hence: either good but bound to be prohibited; or allowed but lousy. The latter I cannot do. I shall probably finish it next week (Schorlemmer  is here again till Monday). There will be fully four printer s sheets or more. If you people want to take the chance after reading it of printing it in the Neue Zeit,  you must assume responsibility for all the blood that will be shed and don t blame me afterwards. But if you exercise prudence and will not risk the whole journal because of one article, then have the thing printed as a pamphlet, either in Zurich or like Die Frau.  That is for you to decide. I believe that thing will be of special importance for our general world outlook. Morgan makes it possible for us to look at things from entirely new points of view by supplying us in his prehistory with a factual foundation that was missing hitherto. Whatever doubts you may still have about details in the history of primitive times and savages , the gens settles the case in the main and explains the history of ancient society. And that is why the thing wants to be worked out seriously, carefully considered, demonstrated in all its interconnections but also treated without paying any heed to the Anti-Socialist Law. There is still another important point: I must show how Fourier s  genius anticipated Morgan in very many things. It is Morgan s work which throws into bold relief the whole brilliance of Fourier s critique of civilisation. And that takes a lot of work...
Letters: Karl Marx and Frederick Engels, Selected Correspondence 1884