The conceptual point of departure is avant-garde theorist Walter Benjamin’s famous essay “The Work of Art in the Age of Mechanical Reproduction,” which concludes that technology is withering the “aura” of art, diluting its ritual aspect and destroying the very concept of “authenticity.” From here Scenario moves on to poststructuralist musings on the problematization of the authorship function and how it reflects the fundamental erosion of the individual’s authority over his own life. If this sounds more like lecture than performance, hang on: all the highfalutin mentation is undercut and underlined (by Polish stage and film actor Jan Peszek) with precise sequences of abstract buffoonery. Like the self-conscious text, the physical commentary is alternately oblique, sardonic, thoughtful, ridiculous–but it has an unbroken, almost musical rhythm that’s mesmerizing. Playwright and critic Boguslaw Schaeffer is best known as a composer, and in a sense the limber, rubber-faced Peszek is both conductor and orchestra for this piece–the “instrumental actor” of the title–dramatizing both the difficulty of making meaningful art and the frustrating art of describing that difficulty. Illustrating such intangibles is a heady task, but Peszek–using nothing but fire, water, flour, Ping-Pong balls, buckets, fishing line, a cello, and every inch of the stage–makes it look easy. His virtuoso turn also happens to be mindless kinetic fun. In Polish with subtitles. Chopin Theatre, 1543 W. Division, 773-278-1500. Through July 29: Saturdays, 8 PM; Sundays, 6 PM. $20.