Although the basic principles of economics are not really complicated, the very ease with which they can be learned also makes them easy to dismiss as "simplistic" by those who do not want to accept analyses which contradict some of their cherished beliefs. Evasions of the obvious are often far more complicated than the plain facts. Nor is it automatically true that complex effects must have complex causes. The ramifications of something very simple can become enormously complex. For example, the simple fact that the earth is tilted on its axis causes innumerable very complex reactions in plants, animals, and people, as well as in such non-living things as ocean currents, weather changes and changes in the length of night and day.

Thomas Sowell