description: The photograph was taken during Jerzy Bereś’s solo exhibition entitled "Jerzy Bereś. Material proofs. Manifestations from the years 1967-92" (Center for Contemporary Art Ujazdowski Castle, Marble Hall, Jazdów Street 2, Warsaw, 10.05-20.06.1993). Photographed by Mariusz Michalski and Barbara Wójcik. Material proof from the manifestation "Ritual of sincerity", Na Piętrze Gallery, Łódź, 04.05.1976. It is a tree trunk slice placed on small blocks. The inscription "altar of sincerity" is visible on the front. Red handprints are pressed onto the slice. A bottle wrapped in cloth with a green leaf painted on it stands on it.