"Cross-cultural reality testing forces people to examine both their own and others' understandings of reality. Most people simply assume that the way they look at things is the way things really are, and judge other cultures' views of reality before understanding them. These judgments are based on ethnocentrism, which closes the door to further understanding and communication. Furthermore, ethnocentric judgments keep missionaries from examining their own beliefs and values to determine which of them are based on biblical foundations and which on their cultural beliefs."