ABSTRACT
This chapter begins with an exploration of Relativity, an impossible-world perspective picture by MC Escher. The first section of the chapter reviews the main ideas of perspective. The next section describes the location of the vanishing points of Relativity and suggests how the picture achieves its effect. Analysis of the impossible world Belvedere uses the Necker cube, an optical illusion that confuses the viewer with what is close and what is far. Ascending and Descending, another impossible world of Escher, uses the Penrose staircase, an optical illusion that gives the impression of a staircase that forms a continuous loop but is always going up. The chapter concludes with a list of exercises and readings.
