1. Movement in Squares

This seminal painting marks Riley’s first major breakthrough into abstraction. Using the simple form of the square, the artist achieved perceptual effects of motion and space that paved the way for her subsequent black-and-white paintings. The compression and contraction of the squares in alternating intervals of black and white cause the shapes to appear to move and recede inward, as if pulled by an unseen force. Movement in Squares and Horizontal Vibration (cat. 2) were among the paintings in Riley’s first solo exhibition at Gallery One in London in 1962, marking the beginning of her reputation as a vanguard painter of perceptual abstraction.