The present work examines the specificity of the cultural relations and social intermediations established by Tony Smith's, Frank Stella and Donald Judd works, by Fluxus's Grup performatic events, by Joseph Beuys's Aktionen, and by Andy Warhol's Pop Art. The text is driven by the hypothesis that such poetics were fundamental for a statutory renewal of the art, obtained, mainly through successive inaugurations of completely new ways of public exchanges. The following years after the end of the World War II demanded serious revaluations which answers until today to the most disparate behaviors. This present selection of works and authors presupposes, in a second plan, the incidence of a significant poetic apex stimulated by moral urgencies. The resulting works of art of this existential configuration stand out, among other so many aesthetic innovations, by an extravagant presentation and a controverted disposition: they fermented the counterculture of the end of the decade of 1960, guided the movements of the following years and fed the post-modernists debates of the last twenty years.