لخّصلي

In the 19th and early 20th centuries, large urban areas began to grow and spread.Although negative aspects such as pollution and urban slums remain serious problems, many urban planners now believe big cities might help solve the problem of Earth's growing population.Many people viewed cities largely in negative terms-crowded, dirty, unhealthy places full of disease and crime.People feared that as cities got bigger, living conditions would get worse.

In the 19th and early 20th centuries, large urban areas began to grow and spread. Many people viewed cities largely in negative terms-crowded, dirty, unhealthy places full of disease and crime. People feared that as cities got bigger, living conditions would get worse. Recent decades, however, have seen a widespread change in attitudes toward urbanization.1 Many experts believe that urbanization is good news. Although negative aspects such as pollution and urban slums remain serious problems, many urban planners now believe big cities might help solve the problem of Earth's growing population.

Harvard economist Edward Glaeser is one person who believes that cities bring largely positive benefits. According to Glaeser, cities are "the absence of space between people." This closeness reduces the cost of transporting goods, people, and ideas, and allows people to be more productive. Successful cities also attract and reward smart people with higher wages, and they enable people to learn from one another. According to Glaeser, a perfect example of how information can be shared in a big city is the trading floor of the New York Stock Exchange. There, employees share information in one open, crowded space. "They value knowledge over space," he says. "That's what the modern city is all about."