"When the relation between all points of a curve and all points of a straight line are known, in the way I have already explained, it is easy to find the relation between the points of the curve and all other given points and lines; and from these relations to find its diameters, axes, center, and other lines or points which have especial significance for this curve, and to choose the easiest. By this method alone it is then possible to find out all that can be determined about the magnitude of their areas, and there is no need for further explanation from me."