But when the artist abandons visible appearance, as in Mondrian's black grids on white grounds filled with balancing rectangles of colour, many people feel left behind. And yet the rhythms of Mondrian are those of nature. The harmonies are those which guided proportion in classical buildings and Renaissance churches. Rothko's glowing maroon Seagram Murals at the Tate may, like Turner's late canvases, appear to be "of nothing" but in their brooding depth Rothko suggests another world. As one four year old child said of the Rothko room at the Tate "it makes me think of God."