Immanuel Kant [1] (1724-1804) was a famous German philosopher who lived in Königsberg in East Prussia (now Kaliningrad, Russia). He was one of the great thinkers of the European Enlightenment. Among his many ideas was his conception of how all knowledge might be organized. Kant said that there are three ways to organize all knowledge: the topical approach, the chronological approach, and the spatial approach.
In reality, few people limit themselves to using only one of these ways of ordering knowledge. Political Scientists may focus on the politics of certain eras or places. Historians may focus on the history of a particular country. And geographers, as we will see, are great synthesists who invariably use the spatial approach in conjunction with topical and chronological approaches. Yet, Kant's three ways of ordering knowledge demonstrates that the spatial approach of the discipline of geography makes geography one of the core scholarly disciplines.