To understand the most important characteristics of a society, one must study its major cities.

The major cities shape the main skeleton of any society. A comprehensive study to these cities can doubly reflect the main characters of the society. All the critical events and the vital institutions pour in these cities.

The major cities define the identity of the society not only because they are inhabited by its highest percentage of citizens but also because these the citizens of the major cities are an amalgam of different culture , habits , traditions , religion , classes , races and even accents. Consequently, if we want to know the main categories of any society, we just can take survey samples of its major cities to have our precise conclusion.

The museums, the cinemas, the theaters, the scientific and literature galleries, the most famous universities and schools, the big factories, the famous companies, space agencies, the major clubs and last but not least the national competitions are held mainly in the major cities of any society representing the main infrastructure of the society. Accordingly, the degree of the development and civilization of any society can be measured upon the degree of the development and civilization of its major cities.

Basically, we wouldn't expect from a society that doesn't pay attention to morally, scientifically and intellectually develop its major cities to take care of its minor ones so we can trust the major cities of any society as an accurate telltale to know how this society looks like.