The present little book is,originally,a part of alarger whole.About 1875,Dr.E. Duhring, pri-vatdocent at Berlin University,suddenly andrather clamorously announced his conversion toSocialism,and presented the German public not only with an elaborate Socialist theory,but alsowith a complete practical plan for the reorganiza-tion ofsociety. As a matter of course, he fellfoul of his predecessors; above all，he  honoredMarx by pouring out upon him the full vials ofhis wrath.

This took place about the time when the twosections of the Socialist party in Germany .Eisenachers and Lassallians — had just effected their fusion，and thus obtained not only an im-mense increase of strength，but,what was more,the faculty of employing the whole of thisstrength against the common enemy..The So-cialist party in Germany was fast becoming a power.But to make it a power, the first condi-tion was that the newly-conquered unity should not be imperiled.And Dr.Duhring openly pro-ceeded to form around himself a sect, the nucleus of a future separate party. It thus became nec-essary to take up the gauntlet thrown down tous,and to fight out the struggle whether we likedit or not.