One of Klein's favorite places for meditation was the basement of a business owned by a friend's father. To mask the claustrophobic quality of the windowless room, Klein created a false sky by painting the ceiling blue. This marked the first time he created a monochomatic painted surface using the color that symbolized limitless space and spiritual purity for him. By 1955, after establishing a Judo school in Paris, Klein committed himself solely to art. In 1956, he held his first major exhibition at the Galerie Colette Allendy. There he showed single-hued paintings which he considered metaphysical fields devoid of emotion.