In the 1970s, Ianelli came to further outline and synthesize his representations by reducing his palette, focusing on different shades of the same color. Asserting formal rationalism as the only adequate language for modern society, Ianelli created collages and insets of mathematically calculated geometrical forms to compose a series of optical games. Ianelli divided his canvas into patterned shapes, seeking a rhythmic relationship between them. His compositions mainly present rectangles and squares, which appear in overlapped and interpenetrating planes that play with transparency and opacity. This phase of his work was influenced by Neoplasticism, including the work of artists such as Piet Mondrian (1872–1944), who emphasized rationality and the importance of proportion, of order and the juxtaposition of colors and rectangular forms. But Ianelli worked with closely-related shades of color, and with more subtle lines and divisions, significantly setting his work apart from, for example, Brazil’s Neo-Concretist painters. In Composição [Composition] (1975) [img. 34], he overlapped rectangles of different shades, emphasizing the geometry created by such a contraposition of hues.
— Guilherme Giufrida, assistant curator, MASP, 2018