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of cyclical process as well; but if so, it is a cyclicity in the sense of periodicity and not in
the sense of a water cycle. Here also, rain over the Earth results from evaporation from
a water surface. A second, more recent, biblical passage of interest is (55,10-11) in the
Book of Isaiah, namely, the following.
This is the very word of the Lord...andastherain and the snow come down from heaven and
do not return until they have watered the earth, making it blossom and bear fruit, and give seed
for sowing and bread to eat, so shall the word which comes from my mouth prevail; it shall not
return to me fruitless without accomplishing my purpose or succeeding in the task I gave it.
Isaiah also lived in the eighth century BCE but this chapter is now generally considered
a later addition and attributed to an unknown prophet, who wrote in Babylon toward the
end of the exile in the sixth century BCE. In this passage the physical phenomena serve
mainly an allegorical purpose and their description is fairly naturalistic; they appear to
occur on their own and not as a result of direct divine intervention. The description
involves unambiguously some kind of cycle by which water returns to where it came
from.
Notions on various cyclical processes were also held in ancient China. In a naturalist
work “Chi Ni Tzu,” probably of the late fourth century BCE (Needham, 1959, p. 467),
atmospheric phenomena are described as follows.
Wind is the qi [or chhi, spirit, mind] of heaven, and the rain is the qi of earth. Wind blows according
to the seasons and rain falls in response to wind. We can say that the qi of the heavens comes down
and the qi of the earth goes upwards.
Because the rain is deemed to originate from the Earth even though it falls from above, the
direct connection between evaporation and precipitation seems to be taken for granted
here.
A passage in the
Chandogya Upanisad
(VI, 10), an important text in Hinduism, which
was composed between 800 to 400 BCE, is less explicit; but it is suggestive of the same
theme. The passage is an allegory to illustrate the essence of the Self or Being (see
Anandatirtha, 1910, p. 458; Radhakrishnan, 1953, p. 460; Swahananda, 1965, p. 458)
and can be translated as follows.
These rivers, my son, flow, the eastern toward the east, the western toward the west. They go from
sea to sea. They become the sea itself, and while there, they do not know which river they are.
This text can be interpreted in different ways. The sentence “They go from sea to sea”
could conceivably refer to sea currents, or to some underground seawater filtration as the
origin of river springs, like that visualized by some in ancient Greece. Still, it is equally
plausible that it refers to the evaporation of these waters from the sea and their subsequent
precipitation back to the sea. The main point is that it implies a cyclical process.
The above descriptions are merely a few examples. A common feature of most of
these early descriptions is that, wherever they imply a water cycling process, they refer to,
or hint at, the atmospheric phase of the water cycle. Wherever evaporation is mentioned
explicitly it is mostly, though not exclusively, assumed to take place from rivers and the
sea. While some of the descriptions include flowing streams, they are silent on the origin
