Rowena Reed Kostellow described the problem as follows:
- "The exercise in convexity is based on organic form and undertakes an exploration in depth of the subtle and involved relationships between the axes of large forms and the expanding planes of the surfaces, and the sensitive lines of the final configuration. This experience often leads to quite beautiful sculptural forms and can help you achieve a high degree of sensitivity and control of organic volumes."
"Convexity is the expression of positive volume or form pushing into negative space. (Concavity is the expression of negative space pushing into positive volume or form.) The characteristics of convexity are weight and bulk. We study convexity and concavity separately and as we learn about one, we learn about the other."
"Our study of the relationship between the axis, the mass and the outline is an exploration of how the mass creates surfaces and how the surfaces result in a silhouette. It’s the opposite of defining volume the way you learned to do it in grade school. Conventionally, we define shape from the outside in by drawing the outline and filling in the space. This problem comes at it from the inside out."