Deterministic reasoning continued in the 19th century when geography itself was related to other sciences. Carl Ritter, a German geographer adopted an anti-human approach and laid the philosophical base of determinism in geography. Ritter tried to make a difference in the physical constitution of the body, body, and the health of men living in different physical environments. Many of his students considered geography as "a study of the relationship between people's density and the nature of their land". Many geographers of their school had declared that their main task was to identify the influence of physical cultural geographical conditions and the political fortunes of residents of any area in both East and present. Alexander von Humboldt, one of the founders of 'Modern Geography' and a contemporary of Ritter (who was also the founder of 'Modern Geography'), also said that the life of the residents of a hill country is different from those in the plains. Friedrich Ratzel, the founder of 'new' determinism, supplemented the 'classical' geographical determinism with the elements of 'Social Darwinism' and developed the state's theory as an organism. He believed in the existence of qualification and saw the 'man' as the end product of development - a development which was a natural selection of type according to the ability to adjust itself to the physical environment of the environment. He along with his disciple Ellen Churchill Semple became the most vocal expression of the deterministic approach to geography.