Why would it be hard to live in a city state

More than half of the population of the world live in cties. Because of this liviing in a city has many down points like:

1.- City life can make us crazy. If you live in a city you have more probability to develop a  mental disorder, 21% increased risk to develop anxiaty disorder, 39% increased risk to develop a mood disorder.

2.- The constant light don't let us sleep.

3.- The air is polluted. It increases the probabilty to develop asthma.

4.- The noise is terrible.

5.- Rush hours are very common.

6.- There are uncaring crowds.

7.- All of these things affect our inmune system.

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