But there is still an additional circumstance. The "system" of Herr Duehring here criticised spreads over a very extensive theoretical ground and I was compelled to pursue him all over it and to place my ideas in antagonism to his. Negative criticism thereupon became positive; the polemic developed into a more or less connected exposition of dialectic methods and the socialist philosophy, of which Marx and myself are representative, and this in quite a number of places. These our philosophic ideas have had an incubation period of about twenty years since they were first given to the world in Marx's "Misere de la Philosophie" and the Communist Manifesto until they obtained a wider and wider influence through the publication of "Capital" and now find recognition and support far beyond the limits of Europe in all lands where a proletariat exists together with progressive scientific thinkers. It seems that there is also a public whose interests in this matter are sufficient to induce them to purchase the polemic against Duehring's opinions, in spite of the fact that it is now without an object, and who evidently derive pleasure from the positive development. I must call attention to the fact, by the way, that the views here set out were, for by far the most part, developed and established by Marx, and only to a very slight degree by myself, so that it is understood that I have not represented them without his knowledge. I read the entire manuscript to him before sending it to press and the tenth chapter of the section on Political Economy was written by Marx and unfortunately had to be somewhat abbreviated by me. It was our wont to mutually assist each other in special branches of work. The present edition is with the exception of one chapter an unchanged edition of the former. I had no time for revision although there was much in the mode of presentation which I wanted altered. But there is incumbent upon me the duty of preparing for publication the manuscripts which Marx left, and this is much more important than anything else. Then my conscience rebels against making any changes. The book is controversial and I have an idea that it is unfair to my antagonist for me to alter anything when he cannot do so. I could only claim the right to reply to Herr Duehring's answer. But what Herr Duehring has written with respect to my attack I have not read and shall not do so, unless obliged. I am theoretically done with him. Besides I must observe the rules of literary warfare all the more closely as a despicable wrong has since been inflicted upon him by the University of Berlin. It has been chastised for this, indeed. A university which so degrades itself as to refuse permission to Herr Duehring to teach under the known circumstances should not be surprised if a Herr Schwenninger is forced upon it under circumstances just as well known.