CHAPTER XL — Critical Commentary & Notes

How the Duodecedron Is Formed in the Ycocedron.

Historical & Mathematical Commentary

• Duality of Icosahedron and Dodecahedron: Just as Cap. XXXVII–Cap. XXXVIII established the dual reciprocity between the cube (6 faces, 8 vertices) and the octahedron (8 faces, 6 vertices), Cap. XL (Campanus XV.6) and Cap. XLIII (Campanus XV.9) establish the dual reciprocity between the icosahedron (20 faces, 12 vertices) and the dodecahedron (12 faces, 20 vertices).

Philological and Folio Apparatus

• 1509 Paganini Witness Folios: 0042 (f. 13v–f. 13v)

• Winterberg 1889 Italian Source: winterberg/01_divina_proportione_italian/040_cap_XL.txt

• Winterberg 1889 German Source: winterberg/03_divina_proportione_german/040_cap_XL.txt

• Marginal Woodcut Diagrams: 0 figure(s) extracted from the 1509 Venice witness.