In  1956 the art historian Ernst Hans Gombrich delivered a series of Lectures in the National Gallery of Art in Washington DC; they are better known by the name Art And Illusion. Among other concepts,  Gombrich explains how in our mind we complete a picture through an “intellectual inference” He gives the example of Van Eyck who trusted his observer to interpret a wooden panel in the painting Music –making Angels, from the Ghent altarpiece, as a detail of an organ.

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The observer could recognize the organ in the panel because of a previous knowledge and experience-- He has seen organs before. Van Eyck trusted that the well-informed beholder “would complete his picture through intellectual inference“(p.212, 1960.) But this is only the beginning, Van Eyck and Gombrich further challenge the observer. If you look closely at the painting you could see at the side of the panel a glimpse of red and brown. Gombrich points out that this is the hair and the garment of an angel who works the bellows. In order to interpret those red and brown colors correctly the observer has to know how the organ works. And Gombrich argues that van Eyck did not want his observer to miss that hint.

I am thankful to Gombrich for his insight of this painting, but I am saddened to think about all the other references that I keep on  missing due to my lack of necessary knowledge and experience.