After World War II, in the first decade of the People's Republic of Poland, science fiction was used as a propaganda tool by the communist regime, with its main purpose being to show the "bright future" of communism. Only after Joseph Stalin's death were Polish writers to gain more leeway and start questioning the reality around them, albeit always struggling against censorship. At that time the undisputed leader of Polish science fiction was Stanisław Lem, who first questioned the regime's actions in his "Memoirs Found in a Bathtub". He was followed by Janusz A. Zajdel, Konrad Fiałkowski and Czesław Chruszczewski, and from the mid-70s for a short period by the acclaimed writings of Adam Wiśniewski-Snerg.