Piaget, in his study of how children think and learn, dealt with schemata and concepts. The schemata is a part of the concept. We talked of trying to measure whether the child has grasped the concepts of color and of shape. We mix together red, blue, and green circles, squares, and triangles. We ask the child to sort them.
Child puts red triangle in one pile, then adds red square.
Color, we think. Child has learned color. But no, the next piece in the pile isa blue square. Looks to us as though child has not learned concepts. Piaget points out that child has part of concept, color, but is distracted along the way by shape.