5 German philosopher Karl Marx was born on this day in 1818.
Although Marx is most famous for his political ideas, his philosophies also contributed indirectly to modern psychology. Embedded in Marx’s doctrine of historical materialism–the study of society, economics and history–is the idea that understanding the human mind relies not only on inward reflection but also on the historical and social context in which a person lives. For Marx, that meant a person’s work life. Today the study of social psychology explores in much greater depth how cultural influences, social status and other factors contribute to a person’s mind-set and behaviors.