Which artist and teacher encouraged Georgia O'Keeffe's early abstract experiments in 1914?

Arthur Wesley Dow encouraged Georgia O'Keeffe's early abstract experiments in 1914.

Dow taught at Teachers College, Columbia University, where O'Keeffe studied. His approach emphasized composition, line, tone, and the expressive arrangement of forms rather than simply copying what the eye saw. Those ideas gave O'Keeffe a framework for developing a more individual visual language.

After encountering Dow's ideas, she produced a series of abstract charcoal drawings in 1915. She sent some of them to photographer and gallery owner Alfred Stieglitz, who exhibited them in New York. This helped launch O'Keeffe's public career.

Robert Henri and William Merritt Chase were also important figures in her training, but they are not the answer to this question. Dow's teaching is especially associated with the shift that led O'Keeffe toward nonrepresentational art and away from conventional academic exercises.