Natural resources only have value in the context of human technology and goals

From Wealth, Poverty, and Politics by Thomas Sowell. Page 13.

Deserts are another geographic factor isolating peoples. The largest of the world's deserts by far is the Sahara Desert, which is a negative factor for the peoples of North Africa but a devastating handicap for the peoples to the south, black Africans in tropical, sub-Saharan Africa. This incomparably vast desert - slightly larger than the 48 contiguous states of the United States - has been for centuries the largest single factor isolating the peoples of sub-Saharan Africa from the rest of the world. The dearth of good harbors in tropical Africa also limited contacts with overseas cultures. As Fernand Braudel put it, "external influence filtered only very slowly, drop by drop, into the vast African continent South of the Sahara."

Despite geographic influences, there can be no geographic determinism because, where peoples are in touch with other peoples, even an unchanging geographic setting interacts with changing human knowledge and differing human cultures that have different values and aspirations, producing very different outcomes at different times and places. Most of what are natural resources for us today were not natural resources for the cave man, who had not yet acquired the knowledge of how these things could be used for his own purposes. There have been vast deposits of petroleum in the Middle East from time immemorial. But it was only after science and technology had advanced to a level that created industrial nations elsewhere that the Middle East's oil became a valuable asset, profoundly changing life in both the Middle East and in the industrial nations.

Individual geographic influences cannot be considered in isolation, since their interactions crucially affect outcomes. The relationship between rainfall and soil is just one example of these interactions. Not only does rainfall vary greatly from one place to another, so odes the ability of the soil to hold water that rains down on it. This crucial ability to hold water is much less in the limestone soils of the Balkans than in the loess soils of northern China. Since climate and soil affect how well different crops can be grown in different places, that has virtually precluded equal prosperity in all regions of the world during the millennia when agriculture was the most important economic activity around the world, and the basis for the urban development of different societies and peoples.