L. L. Zamenhof his honour. In 1959, Unesco honoured Zamenhof in the occasion of his centenary. In 2015 Unesco decided to support the celebration of the 100th anniversary of the death of Ludwik Zamenhof. Zamenhof was 12 times nominated for the Nobel Peace Prize. His birthday, 15 December, is celebrated annually as Zamenhof Day by users of Esperanto. On 15 December 2009, Esperanto's green-starred flag flew on the Google search web page, in a commemorative Google Doodle to mark Zamenhof's 150th birthday. The house of the Zamenhof family, dedicated to Ludwik Zamenhof, and the Białystok Esperanto Centre, are sites of the Jewish Heritage
Ludwik Fleck is difficult because a collective attains over time a specific way of investigating, bringing with it a blindness to alternative ways of observing and conceptualization. Change was especially possible when members of two thought collectives met and cooperated in observing, formulating hypothesis and ideas. He strongly advocated comparative epistemology. This approach anticipated later developments in social constructionism, and especially the development of critical science and technology studies. Ludwik Fleck Ludwik Fleck (11 July 1896 – 5 June 1961) was a Polish and Israeli physician and biologist who did important work in epidemic typhus in Lwów, Poland, with Rudolf Weigl and