How were the incan people able to build their empire in such challenging geography?

Each of the cultures that settled the area, however, learned to adapt to their environment. In doing so they made scientific advances. In the steep mountains, people made terraces for farming. On the coast, they developed irrigation systems so they could farm in the desert. As a result, farming could support large populations both on the coast and in the highlands, where they built cities a full two miles above sea level.

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The relation between human groups and their consequence in the social structure was one of the objects of study of the famous sociologist Karl Marx. Avoiding to enter into ethical questions about the morality of the systems based on his writings, it is worth noting that Marx's notes are interesting, although partial, in what concerns the idea of class struggle. For him, societies throughout history have always developed through the conflict between the dominator and the dominated, the exploiter and the exploited, or, in more objective terms, the capitalist and the proletarian. For him, the development of history is due to this antagonistic relationship. Its logic can also be applied, for example, to race, since in the case of America, for example, Africans figured as an exploited ethnicity and whites as exploiters. Or, in the question concerning the relationship between man and woman, which historically proves oppressive in certain senses.

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