Illustrations
The author is grateful to Gallerie degli Uffizi, Firenze and Maryland College Institute of Art (MICA) for permission to reproduce the following images:
1 Simone Martini and Lippo Memmi, Annunciation with St. Margaret and St. Ansanus (1333) 176
2 Morris Louis, Bower (1958) (Image: bpk / Nationalgalerie, SMB, Eigentum des Landes Berlin / Jörg P. Anders) 177