Environment

Astrology presented a special case of the relationship between the environment and health. According to the archaic theory of the symbiosis of environment and humans, planets were among the elements that exerted an influence on individuals, particularly one's health and the course of one's life. Such a system, already attested in Babylonia at the end of the sixth century B.C.E., was transformed in the Greek world from the fourth century B.C.E. onward, with the development of scientific (observational and explanatory) astronomy: as the passage of planets across the sky was predictable, so was their action on the human body. At the end of the fourth century B.C.E., astronomic astrology encountered Eastern and Egyptian religions (where celestial bodies were personalized and venerated as divinities), particularly with the expedition of Alexander the Great (356–323 B.C.E.) to Persia and India, the conquest and occupation of Egypt, and the creation of Alexandria (332B.C.E.). Astrology had a new meaning: from its abstract mathematical form, it was personalized and transformed into a religion-like practice, in which the action of divinities—that is, of elements of the world—could be solicited and guided to a determined target, provided that ritual forms were duly followed.

Such para-religious practices, which were not incompatible with the official forms of religion of the Hellenistic and Roman world, collided with Christianity. Following the Jewish tradition, indeed, the new religion conceived the world as God's creation. A new literary genre appeared as early as the fourth century C.E., the Hexaemeron (The account of the six days [of creation]), which narrated the whole process of Creation, from the universe to humankind, including the paradisiacal environment. Similarly, a new anthropology developed, first represented by Nemesius of Emesa (fourth/fifth centuries C.E.). Creation included a hierarchy at the top of which was human beings, who had been created in God's image. In this context, there was no place for evolution: Creation was perfect, all the more because the negative forces of the world had been defeated. Humans were entrusted with the mission of governing and preserving the world, because humans were a reflection of God's wisdom. This theological concept had an impact on such scientific questions as the causes of disease and the origin of the therapeutic properties of plants and other natural substances. Neither resulted from natural causes: diseases were inflicted by God as punishment of sins, and plants were curative owing to the grace of God. The materialistic system was abandoned in favor of that proposed by Galen, which was much more compatible with the Christian understanding of the environment, due to its immaterial nature. As a result of this new vision of the world, human beings' relationship with the environment was no longer direct, but mediated through God. Such a triangular understanding, which lasted until the seventeenth century at least, did not prevent, however, humans from studying and knowing the world: such an undertaking reflected human beings' nature as God's creation. The study and contemplation of the environment, and the exploitation of its resources, became occasions for individuals to discover and adhere to the plan of God.