New Science) in 1725, which argued history as the expression of human will and deeds. He thought that men are historical entities and that human nature changes over time. Each epoch should be seen as a whole in which all aspects of culture—art, religion, philosophy, politics, and economics—are interrelated (a point developed later by Oswald Spengler). Vico showed that myth, poetry, and art are entry points to discovering the true spirit of a culture. Vico outlined a conception of historical development in which great cultures, like Rome, undergo cycles of growth and decline. His ideas were out of fashion during the Enlightenment but influenced the Romantic historians after 1800. A major theoretical foundation for world history was given by German philosopher G. W. F. Hegel, who saw the modern Prussian state as the latest (though often confused with the highest) stage of world development. G.W.F. Hegel developed three lenses through which he believed world history could be viewed. Documents produced during a historical period, such as journal entries and contractual agreements, were considered by Hegel to be part of Original History. These documents are produced by a person enveloped within a culture, making them conduits of vital information but also limited in their contextual knowledge. Documents which pertain to Hegel's Original History are classified by modern historians as primary sources. Reflective History, Hegel's second lens, are documents written with some temporal distance separating the event which is discussed in academic writing. What limited this lens, according to Hegel, was the imposition of the writer's own cultural values and views on the historical event. This criticism of Reflective History was later formalized by Anthropologist Franz Boa and coined as Cultural relativism by Alain Locke. Both of these lenses were considered to be partially flawed by Hegel. Hegel termed the lens which he advocated to view world history through as Philosophical History. To view history through this lens, one must analyze events, civilizations, and periods objectively. When done in this fashion, the historian can then extract the prevailing theme from their studies. This lens differs from the rest because it is void of any cultural biases and takes a more analytical approach to history. World History can be a broad topic, so focusing on extracting the most valuable information from certain periods may be the most beneficial approach. This third lens, as did Hegel's definitions of the other two, affected the study