Copyright © One Reed Publications, 2002

Johannes Kepler:
The First "Great Scientist" -- and the Last Great Natural Astrologer
A Chapter from Valerie Vaughan's new book, Earth Cycles

Nature has given us astrology as an adjunct and ally to astronomy.
-- Johannes Kepler

The Historically Revised Version of Kepler

Most people today think of Kepler as a scientist, but despite the attempts of revisionist science historians to conceal his true identity, Kepler was also a serious practicing astrologer. As one scholar has remarked, those who maintain that Kepler did not thoroughly believe in astrology "can hardly have read his essay De Fundamentis Astrologiae Certerioribus (Concerning the More Certain Fundamentals of Astrology), in which he advances for the criticism of philosophers, seventy-five propositions of varying generality, whose soundness he is prepared to defend." (E.A. Burtt, Metaphysical Foundations of Modern Physical Science, New York, 1925, p. 58)

That Kepler approached his study of natural astrology with the same scientific reasoning that he applied to his purely astronomical studies is a fact conveniently overlooked by modern science writers who portray Kepler as an early scientist who was more or less forced to make horoscopes for a living. This prejudiced view is revealed in the comments of J.V. Field, who published a translation of Kepler's De Fundamentis. Commenting on Kepler's study of astro-meteorology, Field wrote, "Kepler's success in obtaining observational confirmation of his belief in the efficacy of aspects [angular relationships between the planets] may be partly due to the subjectivity of the data, but another possible explanation also presents itself -- aspects are so numerous that for any given change one could almost certainly find an appropriate recent aspect."

We note here the translator's assumption that astrology is bogus, that it is merely a belief, and therefore Kepler's success at forecasting must be an accident that requires explaining. Field has twisted the facts to support his scientistic agenda. He describes Kepler as obtaining confirmation for his belief in aspects, rather than recognizing that Kepler came to a rational conclusion after the gathering of evidence. The historical truth is that Kepler made systematic weather observations for at least 35 years, and then made conclusions based on those observations, noting the correlation of planetary aspects.

We note also the choice that Field offers for explaining Kepler's success -- Either Kepler's observations were "subjective" (a criticism which is curiously never raised in the analysis of Kepler's astronomical writings) or the aspects are too numerous to use as criteria for measurement (a criticism not only based on mis-information about astrology, but one which could apply equally well to the vast number of meteorological variables such as temperature, humidity, pressure, wind direction, time of day or season, etc.). Field assumes that Kepler's accuracy in astrological weather prediction can (indeed, must) be explained by some fault; there is no mention whatsoever of the possibility that Kepler's "success" could be the reflection of a real geocosmic connection. There is not even the slightest suggestion, normally granted to the flimsiest examples of modern scientific research, that this might be an interesting idea that needs further investigation.

Considering the fact that these remarks were made by a translator of Kepler's writings, we have to wonder about how "clean" (unbiased) such translations are. If Kepler were alive today, he would certainly wonder why some of his work was raised to the level of scientific "holy writ," while other works were laid aside, ignored and untranslated, or were mis-interpreted as just some silly metaphysical obsession that requires an apology. But then, Kepler was not troubled by the deep schism that apparently torments many modern scientists and causes them to lose their objectivity when presented with evidence that supports astrology.

Kepler was quite aware of the challenges inherent in the practice of astrology, but his aim was to improve the methods, and he warned others not to "throw the baby out with the bath water." Nevertheless, modern science writers continue to deny or make apologies for Kepler's study of astrology. This bias is shown by one of Kepler's biographers, Angus Armitage, who wrote, "It is tempting to adopt a superior attitude towards old-world thinkers and to regard it as a detraction even from Kepler's fame that he, too, should have shared the common delusion [of astrology]. However, it is only through centuries of scientific discipline that we have acquired a fair ability to look in the right direction for the cause of any unfamiliar phenomenon that we wish to explain. ... We should rather commend their high endeavor in seeking for order and meaning than ridicule them for postulating causal connections between phenomena that we now judge to be totally unrelated." (Johannes Kepler, Roy Publishers, 1966, p. 81)

On the surface, Armitage appears to be offering respect, but underneath this is a condescending attitude which we note in the use of the phrase "right direction" to describe where modern science looks. This same expression appears in another biographical piece, "Johannes Kepler in the Light of Recent Research," by E.J. Aiton (History of Science, 1976, Vol. 14, pp. 77-100). According to Aiton, "Kepler's attempt to reform astrology into a rational science based on experience was a step in the right direction and would have led eventually to its [astrology's] demise, as more data became available."

The same kind of assumption -- that rationality and the scientific method applied to astrology will seal its doom -- is taken to its ultimate extreme by G. Simon in "Kepler's Astrology: The Direction of a Reform" (Vistas in Astronomy, 1975, Vol. 18, pp. 439-448). Regarding Kepler's attempt to reform astrology, Simon wrote, "The remedy was clearly one of those which in the end kill the patient."

As the reader may observe, modern proponents of the scientific method can become inflated by the conceit of the "rightness" of their method. While priding themselves as scientists in their objectivity, neutrality, and openness to examining evidence before making conclusive statements, they still somehow know a priori that astrology cannot be supported, no matter what data is presented, and that astrology cannot be reformed (and never will be), even by a scientist of the highest caliber such as Kepler.

The scientistic "logic" appears to go like this -- Science (along with its domain) is by definition "correct"; astrology is by definition unscientific; therefore, astrology is wrong. Not only that, astrology is doomed; its ultimate fate is demise. Scientistic debunkers accuse astrologers of being fatalistic, yet in their absolute belief that astrology will always be wrong, debunkers are themselves exhibiting a fatalistic attitude. Such contradictions suggest that a profound schism exists deep within the psyche of scientistic debunkers -- which may explain their irrational behavior that erupts so violently at any mention of the A-word. A more complete analysis of this schizophrenia can be found in Morris Berman's The Re-enchantment of the World (1981).

Now that the reader has been introduced to the manner in which Kepler's astrology work has been (mis)treated by modern science historians, let us look at what Kepler himself had to say.

Kepler on Astro-Meteorology

Kepler practiced astro-meteorology and made weather predictions for almanacs based on planetary aspects. Kepler recognized quite well, as have most astrologers from Babylonia to the present, that the study of astro-meteorology is highly complex. Kepler also realized, as do modern scientific meteorologists, that weather is created through a combination of factors, including temperature, humidity, air pressure and wind direction. In scientific meteorology, the forecaster understands that although these factors can be isolated and measured individually, they combine in a multitude of ways to produce a particular weather situation. To test one criterion alone (such as precipitation) will not give the entire picture, and no scientific forecaster would ever attempt to make a prediction based on only one factor.

Similarly, the astro-meteorologist knows that testing only one cycle (such as the synodic cycle of the moon) would give rather limited results. Like the scientist, the astro-meteorologist may observe numerous individual factors, but considers them together in making a prediction. The astrologer's approach is complicated by as many factors as the meteorologist's approach, and both are attempting to match their methods to the same complex object of study. One of Kepler's weather forecasts demonstrates how he attempted to weigh the various astrological indicators of weather. In March of 1601, he observed that "there will be thunder due to Sun opposing Mars, although the latitude of Mars detracts from the force of this aspect, yet the clustering of other aspects adds force to it, thus there will be unnatural warmth."

It is important to recognize that astro-meteorology does not (and has never attempted to) forecast solely upon astrological theory without any observation of physical phenomena. Yet this is what astrologers (like Kepler) are accused of by simple-minded debunkers, as we see in the following example.

Concerning the effects of the planets on earth's weather, Kepler recorded his observations in a straightforward manner. "I have seen the state of the atmosphere almost uniformly disturbed when the planets are in conjunction and in other configurations known to astrologers. I have noticed the atmosphere in a tranquil state when there are none or few of such aspects, or when they are transitory and of short duration." Commenting on this statement, the 19th century science biographer David Brewster reflected the arrogance of the "correct" modern view when he wrote in his Martyrs of Science, "Had Kepler been able to examine these hasty and erroneous deductions by long-continued observation, he would soon have found that the coincidence which he did observe was merely accidental, and he would have cheerfully acknowledged it. Speculations of this kind are, by their very nature, less subject to a rigorous scrutiny; and a long series of observations is necessary either to establish or overturn them. The industry of modern observers has now supplied the defect, and there is no point in science more certain than that the Sun, Moon, and planets do not exercise any influence on the general state of our atmosphere."

"Hasty and erroneous deductions"? Kepler began making weather observations in 1593, and he kept a weather diary from 1621 to 1629 and compared his weather records with angular separations of the planets. It was from this empirical inquiry of the natural world that he discovered three new aspects (angular relationships), including 45 degrees and 135 degrees, which were added to the traditional list of five Ptolemaic aspects (0, 60, 90, 120, 180 degrees). In one of his works, Tertius Interveniens, Kepler discussed his weather observations and quoted seventeen examples to support his theory that a conjunction of Saturn and the Sun causes unusual coldness in the weather.

The following are excerpts from his De Fundamentis which concern astro-meteorology. The full citation of Kepler's essay is De Fundamentis Astrologiae Certerioribus (Concerning the More Certain Fundamentals of Astrology), 1602. It has been translated by J.V. Field, who published in Archive for History of Exact Sciences, 1984, Vol. 31, pp. 190-272. Another translation was published by Clancy Publications in 1942. Portions have also been translated and published privately by astrologer Ken Negus.

Kepler first suggests that there are "cyclic journeys in the humours of the earth," giving as an example the 18.6-year period of the moon which sailors say affects the tides, and "if this is so, the laws and periods of the cycles should be investigated by collating observations made over many years, something which has not yet been done." With this remark, Kepler was anticipating the concept of synoptic weather observation and statistical analysis, which would be developed later in the 17th century.

Kepler explained that "All things that consist of humours swell as the Moon waxes and shrink as it wanes. This single effect determines many of the predictions and choices concerning matters of economy, agriculture, medicine and seafaring. Natural philosophers have not yet completely understood the reason for this correspondence. ... The Moon's power is twofold, one part being monthly, depending on the changing phases, and the other part half-monthly, and on that account also half-daily, seen to exert its greatest force in what Physicians call Crises and in the alternating tides of the sea." Kepler is referring here to geocosmic connections and the influence of weather on health, effects which would be confirmed by many later scientific studies.

Kepler continues, "There are two faculties, warming and humidification. ... Heat is assigned to the Sun. ... Humidification is assigned to the moon. ... To this the five planets add something of their own. ... Saturn has an excess of humidity and is deficient in heat. ... Its influence gives wet winters." Kepler goes on to say that "Mars is likened to dry heat; Venus will humidify more than it warms; Mercury produces more heat than humidity. The power of Saturn and Jupiter to humidify is greatest at conjunction or opposition with the Sun and least at the quadratures. Venus and Mercury will humidify the most at superior conjunction (with the Sun) and least at inferior conjunction."

Kepler also considered the planets' effects when positioned at greater or lesser distances from the earth (apogee and perigee). He thought that their power of warming was greater when they were closer to the earth, a factor related to the planets' speed of motion. "When planets move most slowly, they have the greatest effect, and this is why they are so strong when stationary, even when they are at apogee. In this regard, Mercury's station is the most effectual, for this planet, being at other times the fastest moving, loses the most motion. Saturn's station has the least effect, because Saturn has little motion to lose when stationary. The station of Mercury mainly stirs up winds, and in some places, snow or rain."

Kepler recognized that there were long-term cycles that resulted in larger weather effects than that which were explained by planetary aspects. He examined several possibilities, such as the 19-year cycle of the moon and the apparent long-term effects of eclipses. Kepler's own suggestion is that long-term weather effects may be driven by the motions of the planets, but that such effects are not yet completely understood. While Kepler recommends throughout De Fundamentis that observations and records should be made and compared to confirm such ideas, he states that the effect of resonance or harmony of planetary motions "has not yet been confirmed by experience, nor is there yet any way of investigating the relationships." He further states that, "If astrological conjectures prove mistaken, I think they should be treated with indulgence because of our ignorance of the causes. However, such predictions cannot be regarded as pointless because they deal with matters that are, undisputedly, of the greatest utility."

As we shall see in later chapters, many of Kepler's astro-meteorological observations have been confirmed by modern scientific studies.

An Early Link Between Sunspots, Planetary Influence and Weather

Later chapters in Earth Cycles will also cover the 19th century discovery of correlations between sunspots, the motions of the planets, and earth's weather. This geocosmic connection was anticipated by Kepler in Phaenomenon Singulare (1609). In this work, Kepler recorded a detailed report of his sighting of a sunspot. In the spring of 1607 Kepler had been watching Mercury, which according to calculations should have entered into an inferior conjunction with the Sun on May 29. A heavy storm had begun during the evening of May 27, and since Kepler knew that storms were associated with Mercury at inferior conjunction, he thought that perhaps the calculations were inaccurate and that the conjunction was actually occurring earlier than the 29th. He also thought that Mercury should be nearing its node. When the skies cleared on the afternoon of May 28, Kepler attempted to view the sun-Mercury conjunction. In the loft of his house, single sun rays shone through the thin cracks of the roof, and he held a piece of paper against one ray and saw a little picture of the sun, on which there was a tiny black dot. He was certain that this was a transit of Mercury across the face of the sun, but to confirm this he repeated the observation under other conditions. It turned out, however, that what he had observed was a remarkably large sunspot. A few years later, Johannes Fabricius made public the first scientific information on sunspots, which could be seen with the newly discovered telescope. Kepler later wrote that he was "lucky to have been the first in this [17th] century to have observed the sunspots."

This story relates not only how it is possible to see sunspots with the naked eye, but also the complete confidence Kepler had in his astro-meteorological theories, and how this knowledge led him to what might be called by modern scientists a purely astronomical discovery. Thus we see how utterly intertwined natural astrology was (and is) with astronomy.

The Search for Harmony

Many of Kepler's "scientific" discoveries actually came about as a by-product of the work he performed as an astrologer or -- as the scientists like to say -- a "mystic." This process was described by 20th century mathematician Eric Temple Bell. "Undeterred by poverty, failure, domestic tragedy, and persecution, but sustained by his mystical belief in an attainable mathematical harmony and perfection of nature, Kepler persisted for fifteen years before finding the simple regularity of planetary orbits which he sought. ... What stimulated Kepler to keep slaving all those fifteen years? An utter absurdity. In addition to his faith in the mathematical perfectibility of astronomy, Kepler also believed wholeheartedly in astrology. This was nothing against him. For a scientist of Kepler's generation, astrology was as respectable scientifically and mathematically as the quantum theory or relativity is to theoretical physicists today. It is nonsense now, but astrology was not nonsense in the sixteenth century."

As a young man, Kepler had posed for himself three unusual questions -- Why are there only six planets? Why are they arranged the way they are? Why do they move with such periodicities? In his Mysterium Cosmographicum (1596), Kepler showed that the Great Geometer (God) had provided an archetype for the solar system by arranging the planets in a concentric fashion according to the nesting of five regular solids, suitably spaced for the planetary orbits. He sent this manuscript to the Danish astrologer-astronomer Tycho Brahe, hoping to obtain in return better observational data. The cooperation between these two, documented in Astronomia Nova (1609), eventually led to Kepler's discovery of an elliptical orbit for Mars and the law of areas. While science historians consider Kepler's Astronomia Nova to be his most enduring contribution to astronomy, Kepler himself maintained to the end of his life that his organization of spheres and polyhedra was one of his highest achievements.

According to Owen Gingerich ("Kepler and the Resonant Structure of the Solar System," Icarus, 1969, vol. 11: 111-113), "The research on the Martian orbit was in many respects merely an arduous digression from his more profound search for the archetypal harmonic of the universe." Kepler continued to search for the ultimate order of planetary systems in Harmonices Mundi (1619).

Modern science historians have made famous a complaint Kepler once expressed -- that he had to make horoscopes in order to support himself while he studied astronomy. Modern debunkers of astrology have gotten a lot of mileage out of this statement by extending it to mean that Kepler preferred to study astronomy rather than practice astrology. In this regard, it is interesting to compare another statement Kepler made in 1605 in a letter to the Englishman Heydon following several years of struggling with his calculations of the orbit of Mars. Kepler moaned, "If only God would free me from astronomy so that I can concern myself with my work regarding the harmony of the world." Kepler went on to conclude that, since God did not fulfill his request, His faithful servant Kepler had decided to follow "the divine summons to teach people astronomy."

As Kepler was the first to admit, his own birth horoscope was ruled by melancholic, complaining Saturn. It seems reasonable to conclude that he would look upon the dreary work of either astrological or astronomical calculations as equally oppressive. Any serious study of Kepler's original writings will reveal that he handed out criticism in all directions. He bemoaned the mistaken views of both astronomers and astrologers, as well as the superstitious nature of the masses seeking astrological prediction. However, modern debunkers have singled out Kepler's criticisms of contemporary astrological practices and popular fascination with prognostication, and presented these as proof of his outright rejection of astrology itself. They do not see that Kepler's similar wish to be freed from astronomy (in order to pursue harmony) could be likewise misconstrued as a rejection of the whole field of science. The fact is that Kepler rejected neither astrology nor astronomy. In his acceptance of both, he represents an ideal model of the responsible researcher of geocosmic connections.

Copyright ©  One Reed Publications, 2002

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