'Superman': Friedrich Nietzsche, German philosopher, 19th century (1956). Nietzsche (1844-1900) put forward the idea of the √úbermensch (Superman) as an objective for humanity to aspire to in his book Thus Spoke Zarathustra, published in 1883. From the Picture Post Library. A print from 'Ideas, a volume about the origin and early history of many things, common and less common, essential and inessential', by Readers Union The Grosvenor Press, London, 1956. (Photo by The Print Collector/Print Collector/Getty Images)