“Wallis saw Greek diagrams as intricate and confused. His own... clearly displayed the conic sections and the key lines characterizing... their ‘essential affections’... More importantly, he used the same diagram as often as possible and, when not... changed the diagram only minimally. ...[He] claim[ed]... his 1685 Treatise on algebra... considered the sections 'abstractly as Figures in plano, without the embranglings of the Cone'.”