• I can't keep from fooling around with our irrefutable certainties. It is, for example, a pleasure knowingly to mix up two and three dimensionalities, flat and spatial, and to make fun of gravity.

    M. C. Escher: I can't keep from fooling around with our irrefutable certainties. It is, for example, a pleasure knowingly to mix up two and three dimensionalities, flat and spatial, and to make fun of gravity.
    "On Being a Graphic Artist" by M. C. Escher, 1981.