Ancient Hindus had a clear insight into almost all aspects of environment that are conducive to health and happiness of all life forms. They had a clear idea about the environment ideal for human beings to make houses.
An environment or place was considered unsound or unhealthy for making houses and living when:
- Its normal color, smell, taste and touch have been affected
- The place contains excessive moisture
- The place is troubled by reptiles, violent animals, mosquitoes, locusts, flies, rats, owls, vultures, jackals etc.
- It has groves of grasses and creepers and abundance of diffuse plants
- It has a changed look.
- It has dried and damaged crops
- It has smoky winds
- It is uproarious with the cry of birds and animals
- Its animals are in bewilderment and pain
- Its supports a community which is lacking virtues of truthfulness, modesty, conduct, behavior and other merits
- The place has rivers constantly agitated and flooded
- The place experiences frequent occurrence of meteorites, thunderbolts and earthquakes
- It has a harsh appearance
- It frequently shows the sun, the moon and the stars with rough, coppery, reddish white and cloudy appearance.
Inhabitants of open space in isolated forest areas with scanty rainfall and predominately dry winds are generally well built, hardy and healthy.
On the other hand, inhabitants of humid climatic zones receiving abundant rainfall and with marshy lands, deltas and dense forests are generally delicate in physique and health.
Ancient Hindus considered places where people are corrupt and immoral as unwholesome to human health and prosperity.
They had insight about the pollution resulting from living in a place that is overcrowded, where there is too much noise or too much unrighteousness etc.
Bibliography – Encyclopedia of Hinduism Volume IV – page 8