It is the awakened, intelligent, class-conscious Working Class of the World that stands back of the May Day. In America May Day is celebrated by the revolutionary Socialists in the political arena and, besides a few progressive locals of the American Federation of Labor, by the Industrial Workers of the World in the economic arena.[1] Footnote 1: The original Industrial Workers of the World, formed in Chicago in 1905, and having at the time of this writing its headquarters in Detroit, and not the Anarcho-industrialist “Chicago I. W. W.”, is meant in this and subsequent paragraphs. The key-note to May Day is the greatest Truth of the Age, the solidarity of the working class of the world and the struggle for the overthrow of the capitalist class and its wage system. As the Preamble of the Industrial Workers of the World, one of the most compact utterances of a revolutionary workers’ organization, expresses it: “The working class and the employing class have nothing in common. There can be no peace so long as hunger and want are found among millions of working people and the few, who make up the employing class have all the good things of life. “Between these two classes a struggle must go on until all the toilers come together on the political, as well as on the industrial field, and take and hold that which they produce by their labor.... “The rapid gathering of wealth and the centering of the management of industries into fewer and fewer hands make the trades unions unable to cope with the ever-growing power of the employing class, because the trades unions foster a state of things which allows one set of workers to be pitted against another set of workers in the same industry, thereby helping defeat one another in wage wars.... “These sad conditions can be changed and the interests of the working class upheld only by an organization formed in such a way that all its members in any one industry, or in all industries, if necessary, cease work whenever a strike or lockout is on in any department thereof, thus making an injury to one an injury to all.” Fully in keeping with these basic principles are the sentiments and ideas given utterance to at May Day celebrations, as are also the functions and the work of the organizations, both political and industrial, which unequivocally rally under the Banner of the International May Day. Lessons Taught to Labor. On May Day, of all days, the men, women and children of the working class, whatever line of work they may be engaged in in a given industry, are appealed to by industrial union representatives to form one compact union of the workers of the industry, and all such industrial unions to form one nation-wide union of the working class.