by Bruce Scofield
originally published in The NCGR Journal, Winter 2000/2001
The lack of a general theory for astrology has kept it from progressing in a scientific way for over 400 years. Prior to the Scientific Revolution, however, astrological theory was in accord with a prevailing scientific view that included the notion of the Earth as a living, organic system. This idea was central to the elaborate astrological cosmobiology of the Stoics and also that of Johannes Kepler. There is one modern multi-disciplinary scientific view, the Gaia Hypothesis, which approaches the study of the Earth as a kind of living system. Astrology, particularly astro-meteorology and other types of natural astrology, may be relevant to this avenue of inquiry into the nature of our planet.
The Tradition of Natural Astrology
According to Ptolemy, the greatest scientist of the ancient world, there are two major branches of astrology. There is first what he refers to as universal or general astrology, or what later authors refer to as natural astrology. Ptolemy makes it perfectly clear that this branch is not to be confused with astronomy, which is a study preliminary to the prognostic art of astrology. Universal or general astrology is concerned with cities, countries, and races, wars, famines, pestilences, earthquakes, floods, weather in all its manifestations, and variations in climate. We could also add to this list the changes of the tides as influenced by the Moon, this being a part of Stoic astrology of about the same period as Ptolemy. The other major branch of astrology, according to Ptolemy, is called genethliological, or the astrology of individuals.(1)
Today astrology is divided into several branches that include those outlined by Ptolemy. What Ptolemy called universal astrology is generally referred to today as mundane astrology, though it is broken into smaller categories. Genethliological astrology is now known as natal astrology. In regard to today’s mundane astrology, I would argue that astro-meteorology and the astrology of earthquakes and volcanic eruptions might form the core of a modern version of universal or general astrology, referred to from here on as natural astrology. This category should also include the study of the solar cycle and its influence on the Earth’s magnetic field and consequently, life on Earth. The tradition of natural astrology analyzes the planetary configurations of the solar system from both a geocentric and heliocentric persepective. (Unknown to most scientists, the heliocentric approach has long been employed by astrologers in regard to long-term global cycles.) I would also include in this category studies of lunar rhythms on animal life and possibly the ice age cycles proposed by Milankovitch.(2)
Natural astrology (and by association genethliological astrology) had a theoretical framework that was supported by ancient Greek natural philosophy. This key components of this theoretical framework were expressed most specifically in the writings of Ptolemy and Aristotle. It was their discrediting that initiated the present theory-deficient period in the history of astrology. During the 16th and 17th centuries, the geocentric Ptolemaic astronomical model of the solar system was replaced by the heliocentric ideas of Copernicus — a rejection which, by association, put Ptolemy’s astrology in question.
Around the same time, the appearance and close observation of comets and supernova by careful observers like Tycho Brahe led to further doubt about traditional cosmology. Eventually, there was a complete rejection of the ancient doctrine of the multi-layered heavens, as well as Aristotle’s explanations of how the heavenly ether caused effects on the four elements. These cosmological concepts had been used for centuries as a model to explain the effects of the planets on the Earth.(3)
Another major change of the period was a shift in perspective regarding nature itself. Astrology lost its theoretical backing at precisely the same time that European scientists began to view nature as a machine, as dead matter that could be explained mechanically. Prior to this terrestrial de-vitalization, when astrology had a theoretical framework, the Earth itself was perceived as being alive and therefore reactive to the influences of the planets. It is this living element of the ancient theoretical framework for astrology, along with some comparisons with a recent development in modern science, that will be addressed in this article.
In summary, there is a long tradition in astrology, clearly defined by Ptolemy 1,850 years ago, that deals with non-human, geocosmic interactions. Unlike genethliological astrology, which has informed itself with the fruits of research in psychology, natural astrology requires the insights of modern astronomy, meteorology, climatology, biology, and geology.
The Gaia Hypothesis
It is my view that astrology needs to go beyond merely being a practice. It needs to raise its standards, construct an explanation for itself, and rejoin the larger world of scientific inquiry. There may be more opportunities to do this than most suspect. One very interesting movement in science today, and one that resonates well with natural astrology, is the work associated with the Gaia hypothesis. In brief, the Gaia hypothesis proposes an understanding of the Earth as a living, dynamic, and self-sustaining system that can only be studied in a multi-disciplinary way. The study of Gaia requires the insights of biologists, ecologists, chemists of all kinds, oceanographers, geologists, and researchers from other branches of science. Originally proposed by James Lovelock in 1968 and supported by microbiologist Lynn Margulis, this hypothesis is still considered to be radical and controversial by many in the establishment science community.(4)
The origins of the Gaia Hypothesis derive from Lovelock’s work for NASA on the Viking Mars probe’s life-sensing technology. His assignment was to determine exactly what evidence would suggest that a planet was life-supporting. In answering this question, Lovelock was led to the idea of the Earth as a system regulated by life itself.
The challenge was to discover why life exists on Earth and not on other planets. Venus and Mars, being chemically and geologically similar to the early Earth, were long thought to be likely candidates for extraterrestrial life, but both planets have settled into a state that is hostile to life as we know it. Venus is too hot, Mars is too cold, and both have excessive amounts of carbon dioxide in their atmospheres. In contrast, the Earth’s temperature has remained comfortable and stable for several billion years, in spite of the fact that the Sun has grown about 25% hotter during this same period. Further, the chemical content of the atmosphere and the salinity of the oceans has stabilized into proportions that could not occur randomly.
In short, the Earth exhibits a balance of conditions hospitable to life that (a) could not occur by chance, and (b) are apparently maintained at more or less stable levels by organic processes. Biological life, in the Gaian view, acts as a geological force. Roots break down rocks, marine organisms create limestone deposits, and micro-organisms modulate the Earth’s atmospheric chemistry. The key concepts of the Gaia hypothesis are as follows:
The Earth is a single living ecosystem, fueled mostly by the Sun.(5) The countless individual species that live on the Earth function like the organs of a body. Gaia is a system with many regulators. Living organisms have produced and continue to maintain the current composition of the reactive gases of the atmosphere, the temperature of the earth, and the salt content of the oceans. Organisms also incorporate minerals in their being, thus blurring the distinction between living and non-living things.
On a more philosophical level, there are certain aspects of the Gaia Hypothesis that some people find unacceptable. One problem has to do with teleology, the idea that nature has a special purpose or a final cause. Some people assume that the Gaia Hypothesis suggests a creative design in nature, as though there might be some creative “being” or intellect at work. But intentional purpose is not a part of the Gaia Hypothesis. Teleology is an idea that belongs to humans, and humans have no special place or role in the Earth system called Gaia. Humans merely overpopulate and strain the resources of the planet. Bacteria are actually more important as they contribute greatly to the maintenance of conditions suitable for life. The only goal of Gaia, if it could be said to be a goal, is the tendency to perpetuate homeostasis (stability). Further, it appears that Gaia operates opportunistically. If the global ecosystem is disturbed, whether by a large meteor or by human pollution, Gaia will adjust, as need be, with or without human intervention. Some might say, however, that humans are a Gaian development that could eventually serve to deflect collisions with asteroids (through space technology) and thus prevent a mass extinction.
What should be of interest to those working with astrology is that several of these Gaian concepts have precedents in astrological theories from earlier times. From the ancient Greeks to Johannes Kepler, there is abundant evidence that ancient, medieval, and Renaissance astrologers viewed the world as a living animal, comprised of numberless cell-universes, all mutually affecting each other. Such a view was central to astrological theory for over 2,000 years. It offered a way to explain the correspondences between the aspects of the planets and the activity of the air (weather), water (tides), and the rhythms of animal and plant life. From the earliest astrological writings, the notion of a living Earth is found wherever astrological theory has been elaborated on.
Greek Natural Philosophy
About 2,600 years ago, formal Greek philosophy began with the Ionian philosophers of nature. Thales, Anaximander, and Anaximenes were the revolutionary thinkers who used their minds as tools to sort out the varied phenomena of the world and offer explanations for creation and existence. For them, the concept that Earth was one huge organism was never questioned. Their concern was more in regard to how it came into being and what element it was made of. Pythagoras, a later contemporary of the three Ionians, suggested that the differences apparent in nature were due to differences in underlying geometrical structure. Number was at the bottom of reality. This concept, the idea that nature could be understood mathematically, served not only as the foundation for Plato’s famous doctrine of forms, but later became a key component of the modern scientific method.
Like the Ionian philosophers, Pythagoras, Plato, and their followers never really questioned the notion of the living Earth. And, although these thinkers never expressed this directly, they apparently saw no reason why astrology couldn’t play a legitimate part in explaining the cycles and changes that are observable in the life of the Earth. Astrology as we know it was not a native Greek tradition; it originated in Mesopotamia. But when the Greeks found that astrology followed basic mathematical rules (i.e., rules of geometry), they saw it as a logical and legitimate subject. Astrology, then, slipped quietly and naturally into many of the cosmological speculations of the early Greek philosophers.
The way the ancient Greeks actually explained the “astrological effect” hinged on two concepts. The first was the idea that the Earth is a living, animate organism. Plato is generally credited with the establishment of the long-lasting and influential tradition of the “world soul.” In his dialogue Timaeus, in which Timaeus the astronomer speaks at length of the nature of the universe, Plato describes the world as being created as a living being.(6) According to Plato, the world was also endowed with soul and intelligence. Further, the world was not made in the likeness of any individual part of nature, it was simply one living organism, containing within itself all other living things. Being alive, it was responsive to its environment and could therefore respond to the movements of the planets.
The second concept upon which the Greek explanation of astrology depended was that of “sympatheia” or cosmic sympathy. When the cosmos is considered to be alive, with all its parts interconnected and infused with the same universal soul, then we have a situation that can explain how action at a distance (i.e., astrology) can work. For centuries, cosmic sympathy was accepted as the logic behind the astrological effect and was embraced by alchemists, scientists, and spiritual leaders. During the time of the Roman Empire, the Neo-Platonists such as Plotinus (3rd century A.D.) re-stated the Greek concept of sympathy in which the parts within the whole are understood to influence each other, directly or indirectly. The Neo-Platonists taught that the world soul, which extended from the solid Earth all the way to the stars, was alive. Astrology could work because the world soul functioned like an animal. In an animal, bodily parts might be physically remote from each other yet they were obviously in some kind of communication, otherwise sensations such as pain would not be possible. The exact nature of this sympathetic communication was unknown, however, the ancient idea of sympathy might be considered analogous to the modern term “resonance.”
For about 500 years, from the 3rd century B.C. to the 2nd century A.D., Stoicism was probably the most widely-embraced philosophical view in the ancient Mediterranean world. Founded by Zeno in 301 B.C., Stoicism evolved into a tightly organized system that included not only ethics (for which it is most famous), but also a complete metaphysics. Stoicism was a syncretic body of ideas that evolved and stayed current with other intellectual developments in the Greek and Roman worlds. It appealed to a wide range of the population, especially the higher classes and better educated citizens of the Mediterranean world. In this respect, and in regard to its materialistic orientation toward nature, Stoicism could be considered a kind of parallel with our modern, scientific world view. What is especially interesting is that Stoicism fully embraced astrology and explained it using the best concepts available from the many traditions of Greek natural philosophy.
Our knowledge of Stoic philosophy is unfortunately limited. Like many ancient writings, only fragments of the original writings of the major figures in the movement have survived, along with a number of discussions and references to the subject that are found in other contemporary philosophical writings. However, it is known for certain that the Stoics believed that the cosmos was a living, intelligent being.(7) This, as we have already seen, is also found in Plato and his predecessors. Stoicism’s founder, Zeno, gave focus to this concept and taught that the cosmos is a material, biological organism. Further, the cosmic organism was not stupid; it changed and evolved as needed. This Stoic view of the cosmos as living, organic, intelligent, and thus capable of sympathy, has led some scholars to call them cosmobiologists.(8)
The Stoics, in their synthesis of the Greek philosophical traditions, arrived at a concept of nature that embraced astrology and also shared several ideas which are central to the modern Gaia hypothesis. First, Zeno established the Stoic doctrine the idea of the living earth. Later Stoics added that the cosmos grows continuously, gradually incorporating non-living matter into itself. (Both of these ideas are very much in line with the Gaia Hypothesis.) Zeno’s successor, Cleanthes, added that everything alive lives precisely because it has within it heat (fire), which is the vital force of the universe. The Sun, the governing part of the larger Earth organism, was said to be pure fire. This fire was described as “craftsmanlike,” a kind of fire that developed and evolved methodically. The Stoics also thought of this fire as a kind of material god or deity; in other words, God was not something apart from the creation. In modern terms, the Stoic “craftsmanlike fire” might be understood as a kind of “intelligent energy.”
The notion of cosmic fire that is so central to Stoic natural philosophy accounts for both the “living” qualities of the world and the process of creation and destruction. Since fire is capable of transformation, the universe itself was explained as a pulsing, cycling organism that is eternally created and destroyed. According to Stoic doctrine, the world (or nature) cannot completely die. Periodic destructions, which occur according to long-term cycles timed by the planets, bring the world to a conflagration, which is then followed by rebirth and a renewal of growth. This latter idea was derived from the Pythagoreans.
For the Stoics, astrology was a completely logical system that demonstrated an inherent intelligence in nature. The greatest of the Stoic teachers of nature and astrology was Posidonius of Rhodes (ca. 135-51 B.C.). The few surviving fragments of his writings show him to have had a wide-ranging and synthetic view of the world, and his influence on many Roman intellectuals, including Seneca and Cicero, is well documented. Posidonius was also a natural scientist who showed that the Moon pulled the tides, which he regarded as proof for astrology.(9) Again, the “mechanism” for astrology’s effects was sympathy, which explained how planetary movements could influence the various, and not obviously related, parts of the living earth.
Stoicism and astrology were mutually supportive. The former provided the general theory while the latter provided what was then concrete evidence that the world was the way the Stoics said it was, alive and intelligent. There was, however, a very fatalistic element in Stoicism that found support in astrology as well. The notion that one should endure and yet also perfect one’s own fate is directly related to astrology. Those who work seriously with astrology understand the dual importance of both accepting one’s horoscope and taking responsibility for the destiny path that it suggests, but this is a complex issue that has not been well understood by critics of astrology, particularly those of the Christian persuasion. Still, Stoicism was the most comprehensive philosophical system in antiquity that not only embraced astrology, but also offered a kind of general theory of astrology which itself embraced the notion of the earth as a living organism.
With the rise of Christianity, Stoicism declined, and eventually philosophy in Europe became mostly theology. During the Middle Ages, astrology was disempowered as ancient knowledge was lost or rejected and the Earth came to be regarded as something that God gave to humans in order to do with as they saw fit. The view of the Earth as a thing to manipulate probably spurred the evolution of machines, which had not been common in the ancient world.
Then came a time, which we call the Renaissance, when the secular knowledge of the ancient world was rediscovered. Plato and Aristotle were revived and discussed intently, but after 1,200 years of Christianity and the doctrine of the Afterlife, nature and spirit had become separate and distinct entities in the minds of most people.(10) The reigning view was that Earth was dead, but spirit was alive.
It was this intellectual climate, one in which nature eventually came to be seen as little more than a machine, that spawned modern science. Furthermore, most of the founders of modern science reacted against the teachings of the ancients. Copernicus demolished the views of Ptolemy when he argued that the Earth was not in the center of the solar system. Tycho Brahe argued that the solid spheres of Aristotle’s universe were not solid because they were being pierced by comets. Then there was Descartes, the real voice behind modern science, who boldly proclaimed the new ruling paradigm — that ancient knowledge was useless and that nature, a mere machine, was dead. In the midst of this confusing intellectual transition was Johannes Kepler.
Johannes Kepler and the Living Earth
Kepler, who was a brilliant mathematician and practicing astrologer, stood quite literally at the brink of the ancient and modern worlds. He was influenced by both the ancient Greeks and Copernicus. Almost a century after the heliocentric system was first proposed, Kepler was still ahead of his contemporaries in not only supporting it, but validating it as well. His mathematical solutions to the problems of planetary movements have insured his reputation as a hero of modern science, but the real Kepler was more of a Pythagorean.
Kepler considered his most important work to be the construction of a grand cosmological synthesis that accounted for the effects of the planets on the Earth. This synthesis included the notion the earth is alive — it had to be alive in order for astrology to be explainable. In his writings, Kepler strove to reconcile Pythagorean geometry, musical tones, the Platonic world soul, astrology, and the orbital mathematics of the planets. His first work, the Mysterious Cosmos, introduced his grand scheme. His second major work, The New Star, was more strictly astronomical and offered proofs for the orbits of the planets. His third major work, the Harmony of the World, continued the thesis of his first book. In it, he laid out his grand synthesis, which he was then able to support with mathematical proofs. Kepler was not like Galileo. He was not doing experimental science, he was actually a very sharp mathematician practicing a kind of Pythagorean astrology. He even saw himself as the successor to Pythagoras and Plato.
In addition to his three major books, Kepler wrote a number of short works in which he expressed his ideas on astrology. In one of them, a work published in 1602 called Concerning the More Certain Fundamentals of Astrology, he states that the Earth’s animate faculty is aroused by the geometry of the planetary aspects.
“…We believe that there is an enlivening animate power in the Earth, and that in the animate power there is some sense of geometry, because this power is of the kind of animate faculty, which, although it always applies itself to its work, is stimulated in a higher degree when nourished, as it were, by harmonious aspects.”(11)
Not only was the Earth an animate being, it was, according to Kepler, capable of a kind of intelligence that supported his astrological observations. He thought the living Earth had a sense of geometry, that it could “hear” the aspects made by the planets as they moved in their orbits. In other words, the astrological effect was not mechanistic, it was a case of resonance, or as Posidonius might have said, “sympathy.”
In the Harmony of the World, Kepler elaborates in some depth on the idea of the living Earth. First he comments on the Timaeus and the Platonic doctrine of the world-soul. In Kepler’s view, the soul of the universe was located in the Sun. As for the Earth, the effects of astrological aspects on the weather are proof enough for him that the Earth is alive. This is a crucial part of Kepler’s thesis, and one that has been overlooked by historians of science.
For thirty years, Kepler kept a weather diary and compared the weather with the astrological aspects at the time. This practice wasn’t anything new in astrology because correlations between planetary aspects and weather had long been part of the astrological tradition, but Kepler needed this scientific data to support his thesis. If the planetary aspects did coincide with weather on the Earth, and his data proved this, then were they causing the weather through some kind of mechanism, or was the Earth simply responding, or resonating, to the geometry of the aspects? If it was the latter, as Kepler maintained, then the Earth must be sensing them, and sensing implies a living being.(12)
Kepler’s astrological theory had its roots in ancient Greek natural philosophy, but it was also similar in many ways to the notions of the Stoics. What was different was his special attention to geometry, specifically the planetary aspects, and the response that the Earth had to these geometrical alignments. Essentially, Kepler was taking the ancient notions concerning the living Earth and astrology a step further. For Kepler, sympathy was a process that functioned according to the principles of mathematics, and the Earth was an intelligent being that could distinguish between the angular separations of the planets.
Ancient astrological theory, from Stoicism through Kepler, held that the Earth was a living, organic being that responded to the movements of the planets. This rationale applied particularly to the branch of astrology which Ptolemy called universal or general (natural astrology), the branch that includes what is known today as mundane astrology but also deals with climate and weather, earthquakes, and tides. The ancient Greeks explained the “astrological effect” through the concept of sympathy, that all parts of the living cosmos were interconnected. Kepler took this idea in a more mathematical direction. He proposed a kind of resonance theory, that the living Earth could hear or sense the astrological aspects. His proof for this theory was his weather data, a multi-year correlation between planetary aspects and the weather.
The rise of modern science, which demolished Ptolemy and Aristotle and defined the Earth as a machine, left astrology without a supportive theory. During the twentieth century the practice of genethliological astrology, i.e. natal astrology, has dominated the field. Due to its extremely complex nature, scientific explanations to support the claims of this branch have been, more or less, non-existent. This does not mean that explanations do not exist, it’s more likely that science has yet to create a framework in which the workings of astrology can be seen to be reasonable and expected. At present, however, astrologers have abandoned the search for a general theory and have turned towards metaphysical explanations for the subject. The field has also concentrated on the problems created by the practice of astrology in society. As a result, natural astrology has been neglected. This is unfortunate because it is in this area that a starting point for a modern, science-based astrological theory might be found.
Only recently has a movement in science begun to accept a view of the Earth that may offer a starting point for a new general theory of astrology. The multi-disciplinary Gaia Hypothesis understands the Earth as a living, dynamic, and self-sustaining system driven by the Sun. Astrology, which posits a solar and planetary influence on Earth systems, appears to be very compatible with this perspective. With its traditions of planetary configuration analysis, its models of developmental change that operate fractal-like on many levels, and its general function as a mapping technique for dynamic systems, astrology may find a place among the collection of sciences that now study Gaia.
(1) See Ptolemy, Tetrabiblos: Book II-1. Translated by F.E. Robbins. London: Harvard University Press, 1940, and Robert Schmidt’s introduction to the Tetrabiblos: Book I, Berkeley Springs, WV: The Golden Hind Press. 1995. page 1. Ptolemy’s distinction between general-univeral astrology and genethliological astrology was expressed, for the most part, during the Renaissance with the terms natural astrology and judicial astrology. See Allen, Don Cameron, The Star-Crossed Renaissance. New York: Octogon Books, 1973, pp.148, 149.
2) Early in the 20th century, a Yugoslav mathematician and astronomer named Milutin Milankovitch identified three primary cycles based on the Earth’s orbital and axis deviations that together could account for the regular occurrence of ice ages. These cycles are a 23,000-year precession cycle, a 41,000-year obliquity tilt cycle, and a 100,000-to-400,000-year cycle of orbital eccentricity. His theory was ignored until the 1970s when deep-sea cores confirmed his calculations. Today Milankovitch is cited in every major geology text book. When climate change is based on astronomical cycles, is this not a kind of natural astrology?
(3) The ancient doctrine of the concentric spheres, from the change-prone sublunary to the highest, purest, and unchangeable sphere of the fixed stars, served not only to contain the “cosmic-organism” but to also explain the workings of astrology. In the Aristotelian view, the ether of the highest sphere impacts the lower spheres, especially the earth itself, through the modulation of the four elements. The appearance of a supernova in what was believed to be the eternal, unchanging sphere of the fixed stars was a major blow to the basic doctrines of ancient astrological theory. See Arthur Koestler, The Watershed, New York: Anchor Books, 1960, p.92. There are differences, however, between the Aristotelian doctrines of cosmic influence and those in Ptolemy’s “Hypotheses of the Planets.” See Ptolemy, Tetrabiblos: Book I, Translated by Robert Schmidt, Berkeley Springs, WV: The Golden Hind Press. 1995. p. 3 and pp. 50-57. See also Tamsyn Barton, Ancient Astrology. London: Routledge, 1994, pp. 102-113.
(4) See Lovelock, J.E., The Ages of Gaia: A Biography of Our Living Earth. New York: Norton, 1995.
(5) The only exception to this are the ecosystems of the deep ocean vents which are fueled by the heat of the Earth’s interior. Ultimately, however, this energy originated with the formation of the solar system out of the proto-Sun itself.
(6) Plato wrote, “For the original of the universe contains in itself all intelligible beings, just as this world comprehends us and all other visible creatures. For the deity, intending to make this world like the fairest and most perfect of intelligible beings, framed one visible animal comprehending within itself all other animals of a kindred nature.” (Timaeus 30, d. Translated by Benjamin Jowett in The Collected Dialogues of Plato, edited by Edith Hamilton and Huntington Cairns, Princeton, NJ: Princeton University Press. 1961.)
(7) See David E. Hahm, Origins of Stoic Cosmology. Columbus, OH: Ohio State University Press, 1977, pp. 200 ff.
(8) Ibid, p.136 ff
(9) Posidonius was more of a hands-on scientist than a logical speculator. He traveled to the Atlantic Coast at Gades (Cadiz) in Spain, where he observed the correlations between the Moon and tides and stated that this phenomenon was proof of astrology. Apparently, the effect of the Moon on the seas was a controversial issue at the time because the feeble tides of the Mediterranean were not sufficient to convince the skeptics. Posidonius also determined the circumference of the earth. Although he used a faulty formula, he came up with the right answer. He also thought of the Sun as the cause of much of what happens on earth, and he regarded it as being much larger than the earth. Galen called him the most scientific of the Stoics.
(10) Neoplatonism had a strong influence on Christian thought. Plato himself taught that material nature was “informed” by abstract principles. After Plato there were philosophical debates over whether the non-material forms were immanent in nature (an essential part of nature) or transcendent (arising from outside of nature). Although Plato’s mature thought on the subject took into consideration two kinds of forms, one immanent and the other transcendent, the concept of something “higher” and non-material pulling inanimate matter towards itself was exactly what the Christian religion needed to justify itself to intellectuals, for according to the Bible, Yahweh, the Judeo-Christian god, was above and beyond (outside of) nature.
(11) Kepler, Thesis 43, Concerning the More Certain Fundamentals of Astrology (1602). New York: Clancy Publications, 1942.
(12) As further support for this living Earth theory, Kepler cited a number of Earthly attributes that together constitute a kind of foreshadowing of the Gaia Hypothesis. He speculated on the Earth’s self-regulation. He saw a perpetual renewal of water through evaporation that “fed” the Earth. He did not see sharp distinctions between the inorganic and organic products of the Earth, and he saw the tides as evidence of the Earth’s breathing, an idea that may not be so far-fetched when one considers that the Moon not only affects the water itself, but seems to move a large range of organisms. See Chapter VII of Johannes Kepler, The Harmony of the World. Translated by E.J. Aiton, A.M. Duncan, & J.V. Field. Philadelphia, PA: American Philosophical Society, 1997.