“By virtue of color, I experience a feeling of complete identification with the space, I am truly free.” (Passoni, A., ed., Yves Klein, exhibition catalogue, Turin: Galleria Civica d’Arte Moderna, 1970). Klein created numerous monochrome paintings until he came to concentrate on a single color, a particular blue. He wanted to obtain a saturated and luminous hue, without any alteration, which would be extra-dimensional and able to represent all the primary elements of the universe, in particular the opposition of water and fire. “Blue is beyond any dimension, unlike other colors.” (Ibid., p. 31). He felt that the color had to inhabit real space outside and beyond the canvas. [...]