Final answer:
George Murdock was the first to define the concept of cultural universal, identifying various common elements in human societies, including humor. Karl Marx is known for his belief in society's history of class struggle.
Step-by-step explanation:
The first person to define the word cultural universal was anthropologist George Murdock. In his research, Murdock explored various systems of kinship across the world and identified elements that are common across all cultures, which he termed cultural universals. These elements include basic human survival needs like food, shelter, and clothing, as well as shared human experiences such as birth, death, illness, and healing. Murdock's extensive list of universals also encompasses language, personal names, and even jokes, highlighting humor's role in relieving tension and fostering social unity.
For the second part of your question, the person who believed that the history of society was one of class struggle is Karl Marx. He is renowned for his works that analyze society in terms of the conflicts between different social classes.