Plotinos: Complete Works, v. 3 / In Chronological Order, Grouped in Four Periods

by Plotinus

STUDY OF GEOMETRICAL FIGURES.

The method of classification adopted for numbers may be applied to sizes, and thus distinguish the line, the surface, and the solid or body, because those are sizes which form different species. If besides each of these species were to be divided, lines might be subdivided into straight, curved and spiral; surfaces into straight and curved; solids into round or polyhedral bodies. Further, as geometers do, may come the triangle, the quadrilateral, and others.