Snelson is no longer considered a minimalist, but because he is not obviously part of any school, he tends to get left out of the art history canon. Mark Daniel Cohen, an essayist, art critic, and longtime admirer of Snelson's work, believes, however, that it is part of a tradition: the "demanding, erudite, and arcane" field of mathematical art. This tradition extends back to the Italian Renaissance artist and mathematician Piero della Francesca, who explored geometry in his drawings, and includes the pioneers of geometric abstract painting Kasimir Malevich (1878-1935) and Piet Mondrian (1872-1944), as well as contemporary artists, most of them obscure. (A 2000 show on mathematical art at New York City's Cooper Union assembled work by 26 of these artists, Snelson included.) Piero della Francesca's Flagellation is shown here.