"Christian Weise (30 April 1642 – 21 October 1708), also known under the pseudonyms Siegmund Gleichviel, Orontes, Catharinus Civilis and Tarquinius Eatullus, was a German writer, dramatist, poet, pedagogue and librarian of the Baroque era. He produced a large number of dramatic works, noted for their social criticism and idiomatic style. In the 1670s he started a fashion for German "political novels". He has also been credited with the invention of the mathematical Euler diagram, though this is uncertain." - (en.wikipedia.org 18.04.2021)
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