Egocentrism refers to only viewing things from your own perspective or viewpoint. Piaget argued that children in the preoperational stage of intellectual development are egocentric and tested this using the ‘three mountains task’ where the child was asked to identify the photograph that represented what the doll would see from another point of view/perspective. At age 4 (still in the preoperational stage), a child would choose the photo that showed their own view of the mountains, but by age 7-8 (concrete operational stage) they could choose the photograph that represented the doll’s view, showing that they could take another’s viewpoint.