Urbanism is the state of human settlement with high population density, fast pace, personal anonymity, ethnic diversity and other such characteristics.
The dangers which threaten existence in an urban environment are such that man needs a secluded refuge today as much as his primitive ancestors did. He is assaulted by a multitude of sensations he would like to exclude from the space he needs to reserve for his own use. Subjection over a long period to vibrations and sound can be psychologically damaging; vibration, in fact, contributes to neuroses. Odours, mostly from industrial sources, can be not only disagreeable but positively harmful. Pollution in general is not only a danger to health but is also psychological menace.
Modern urban housing, even if reasonably priced and providing the desired conveniences, is often a source of sociological and psychological problems. Concentration, memory, self-confidence, creative thought, and contact with neighbours and with nature decrease; aggression, anxiety and tension increase. Equally, the fear of being overheard by others can cause nervousness. The large panes of glass necessary to meet minimum requirements of natural light can increase the anxiety of people who fear prying eyes and the invasion of their private lives.
Crowding makes the pursuit of hobbies that involve space, dirt or noise almost impossible. The green spaces provided by most cities are inadequate and insufficient to fulfil the population's requirements for contact with nature, leading to such effects on personality as: gradual diminution of initiative and creative thought; loss of sensitivity to primary values; false intellectualism; psychosis and psychic tension; emotional disturbances; negative attitudes. In addition, few people and few families are capable of standing the strain of constant adaptation which the mobility of the modern wage-earner often demands.