Yellow Red Blue, by Wassily Kandinsky.
After attending a performance of Wagner's opera Lohengrin in St. Petersburg, Kandinsky said, "I saw all my colours in spirit, before my eyes. Wild, almost crazy lines were sketched in front of me."
Kandinsky was describing his experience of a condition called tone-colour synaesthesia, in which sounds elicit visual sensations. In his paintings, Kandinsky tried to evoke the visual equivalent of a symphony.
The word synaesthesia comes from the Greek roots syn, meaning 'together', and aesthesis, meaning 'sensation'. The condition was first described in 1690 by the philosopher John Locke, after he encountered a blind man who claimed to experience the colour scarlet whenever he heard the sound of a trumpet.
Synaesthesia was once believed to be extremely rare. However, there is evidence that the condition is far more common that was previously thought.
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