Comments by "" (@neutronalchemist3241) on "Leonardo da Vinci: The Renaissance Man" video.

Leonardo was one of the most prolific writers of his time. He left tons of written sheet of paper (and what we have now is estimed to be only 1/4 of his production), and many of those contains the preparatory works of his paintings. More, Leonardo was famous in his times, and there are tons of contemporary references about his work and about more trivial things (bureaucratic requirements, legal disputes...) Many copies of his paintings were made when he was still alive.
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