William Degouve de Nuncques was a symbolist painter from Belgium. His paintings often contain a mystical element or a visualization of the invisible.
He stayed in Mallorca between 1900-1902 and supposedly had a great influence on Joaquim Trinxet Mir.
Badia de Palma, oil, William Degouve de Nuncques, 1900
According to Wikipedia he is supposed to have said:
To make a painting, all you need to do is to take some paints, draw some lines, and fill the rest up with feelings.