ABSTRACT
The presence of the Portrait of Luca Pacioli and Gentleman (Museo Nazionale di Capodimonte, Naples; hereafter referred to as Portrait ) at the important exhibition Dürer-German Master confi rmed the popularity of this painting among curators and the general public. 1 Even though not a great masterpiece, the Portrait enjoys a sort of iconic status. Thanks primarily to the many mathematical references it contains, it appears “modern” and familiar to the general public, who may also consider it an epitome of the achievements of the Renaissance, as linear perspective, naturalism, printed books, and the rebirth of the scientifi c knowledge of the Ancients are all themes present in the Portrait . In spite of the broad appeal, its contents remain poorly understood. Recent research has detailed the connections between its iconography and mathematical humanism and brought into clearer focus the mathematics displayed in the panel. Building on these results and hoping to advance our understanding of the Portrait , this chapter addresses two outstanding puzzles: the numbers and line segments on the bottom left of the tablet and the addition problem on the bottom right, and the two remarkable solids appearing respectively in the lower right and upper left. The numbers and segments on the tablet will be shown to relate to different powers of the golden ratio, while the solids will be analyzed on their own terms and their presence explained contextually from the perspective of the history of complex geometric solids in the Renaissance. The present study confi rms that the iconography of the Portrait (Figure 8.1) was carefully composed by Pacioli, at a moment-retrospectively-that marked a turning point in his life: after 1495, the friar will transform himself from itinerant teacher of introductory and classical mathematical knowledge into courtier and creator of new and exciting mathematical insights, which eventually bore fruit in the pages of the Divina proportione.
