Conceptual change is described as a multifaceted process involving restructuring and reorganization of already embraced beliefs. Twenty-nine preschool children were interviewed about their conceptions of the earth every year from the year they were four to the year they were six years of age. For the children the incentive for changing ideas about the earth was their processing of incoherencies. The children processed a lot of conflicting information. However, there does not appear to be any major conflict that causes the process of conceptual change to occur. This process is affected by incoherencies revealed in a relation between three entities, that is, two or more different facts or conceptions that conflict when related to one specific context. Conceptual change involves a simultaneous processing of information and complex conceptions, on the one hand, and revisions and changes at a model level on the other.