All early civilizations were located in the tropics or sub-tropics. In these regions nature is dangerous to man. Earthquakes, tempests, hurricanes, pestilences prevail. Consequently, the imagination of man takes exaggerated forms. The judgment is overbalanced; thought is paralyzed. The mind is continually thrown into a frantic state. These reactions throw human life into feeling molds, into poetic rather than scientific forms. Religious feelings are promoted. The leading religions of the world originated in the sub-tropical and tropical regions of the earth. East Indian literature and thought illustrate the effect of nature upon the feelings and the imagination. The works of the East Indians on grammar, law, history, medicine, even on mathematics, geography, and metaphysics are nearly all poems.[XV-11] Prose writing is despised. The Sanscrit language boasts of more numerous and more complicated metres than can any European tongue. The East Indian literature is even calculated to set the reason of man at defiance.[XV-12] The imagination, for example, in India has produced an exaggerated respect for the past; it is this situation which has led poets to describe a Golden Age in the remote past. In the literature of India there is recorded the statement that in ancient times the average length of life of common men was 80,000 years. There are instances of poets who lived to be half a million years old. In Greece, on the other hand, nature is more quiet and the mind of man functioned in a reasoning way. In the North Temperate zone science developed. “The climate was more healthy; earthquakes were less frequent; hurricanes were less disastrous; wild beasts and noxious animals less abundant.”[XV-13] Buckle, in other words, insists that everywhere the hand of nature is upon the mind of man. The work of Buckle, the chief exponent of the influence of physical nature upon mental man, accentuates important phases of the growth of civilization. Buckle over-emphasized his anthropo-geographic observations. However, they constitute a part of the whole picture of human progress, and when seen in the light of modern mental growth and control of environment they shrink into proper proportions. The field which Buckle opened has been developed extensively by Friedrich Ratzel (1844–1904). This German scholar, traveler, and geographer is generally credited with putting anthropo-geography on a scientific basis. Miss Ellen Semple attempted to translate his work on _Anthropo-Geographie_ into English, but found the German constructions so difficult to handle accurately that it was necessary for her to put Ratzel’s observations into her own words. She also points out in Buckle a lack of system and an undue tendency to follow one generalization after another. Her own _Influences of Geographic Environment_ has now become a standard work on the ways in which physical nature affects mankind.