Final answer:
A personally or socially preferable mode of conduct or state of existence that tends to persist over time is called a societal value. Ethnocentrism is the belief that one's own culture is superior to others, which can lead to prejudice and impedes cultural understanding and a tolerance for cultural diversity.
Step-by-step explanation:
A personally or socially preferable mode of conduct or state of existence that tends to persist over time is called a societal value. Ethnocentrism, as described by sociologist William Graham Sumner, involves a belief or attitude that one's own culture is better than all others. It's a common human tendency, where, for example, we might refer to another culture's practices as 'wrong' rather than simply different. This can lead to the unjust assessment of other cultures solely based on the standards of one's own culture, often without acknowledgment of the context or values of other societies.
Moreover, ethnocentrism is not just about comparing cultures but can extend to a belief in the superiority of one’s own nation or ethnic group over others, leading to discrimination and prejudice such as xenophobia. This belief system is in contrast to cultural relativism, where one assesses a culture based on its own standards and values. Understanding the difference between ethnocentrism and cultural relativism is crucial for fostering tolerance and appreciating cultural diversity.