Chapter 4
GALILEO, ASTROLOGER'If, as little as a century ago, it had occurred to anyone to demonstrate that Galileo was a judicial astrologer, he would certainly have been persecuted as a sacriligious person. With so much art was the veil drawn over all that might give credence to the idea that this was a weakness of the great philosopher... that for ages no-one would have dreamed that the great reformer had failed to keep clear of that fatal influence'.
Antonio Favaro, 18811
No published work about Galileo in the English language admits that he was, in effect, an astrologer. One will scarcely find any mention of the subject, except for claims that he held an attitude of scepticism towards it. Yet, Antonio Favaro, editor of the complete 20-volume Works of Galileo and Italy's major expert on the subject, composed in 1881 his essay, 'Galileo Astrologo' and this concluded:
'It seems to me impossible to have the slightest doubt that Galileo was involved with astrology, indeed, that he was famous for his great ability in that art, so that distinguished people consulted him with complete confidence, in many cases asking for horoscopes and predictions2.'
For comparison, a typical modern opinion is that 'Galileo's opinion of the theory that the tides are caused by the moon was terse and definite: 'Astrological nonsense,' expressed by Eysenk and Nias3. Galileo never expressed such a view, or anything resembling it. I presented a paper on this topic to the 'Galileo 2001' international conference, and have come across no evidence that he ever doubted the truth of astrology.
Research by the Italian astrologer Grazia Mirti, editor of Linguiccio Astrale, has re-opened the subject for the twentieth century. She was invited to present her findings at the 1992 UK astrology conference4, and then published these in her Italian journal5. In that year, quattrocentenary celebrations were held in the city of Padua, commemorating Galileo's acceptance of the city's chair of mathematics lecturer in 1592, after having held a chair at Pisa. The British address by Mirti was thus a distant echo of these quattrocentenary events. Mirti has recovered the remains from a severe process of censorship, through centuries in which Galileo was cast as the icon of a materialistic science. Twenty-five charts drawn up by Galileo are all that remain, plus three instances of his chart analyses6. The book from which he learnt his astrology while at Pisa may have been Porphyry's Introductio in Ptolemaei opus de effectibus estrorum...' of which a copy annotated in his hand remains at Florence7.
The Dimensions of Hell
As regards what it meant to be a citizen of Florence in the Renaissance, immersed in the culture of Dante, we may consider how, as a 24-year old, Galileo gave in 1588 two lectures to the Florentine Academy on 'The Shape, Place and Size of Dante's Inferno'. These boldly 'attempted to determine certain physical characteristics of Dante's Inferno'. While the heavens visible to the senses had all been mapped out,
'how much more wonderful should we consider the study and the description of the place and size of hell which lies in the bowels of the earth, hidden from all the senses and by experience known to no-one8.'
From such considerations we may in some degree readjust the view expressed by Arthur Koestler, who disliked Galileo as a character, finding him 'wholly and frighteningly modern9'.
A Mathematicus
Like Kepler, Galileo was a mathematicus, a word meaning simultaneously mathematician, astronomer and astrologer. Thus, Copernicus' opening paragraph of his De Revolutionibus referred to 'this art - which some call astronomy, others astrology, and many of the ancients the consummation of mathematics.'10 That unity disintegrated shortly after their era, but was then still intact. This vital dimension was wholly omitted in Brecht's play 'Galileo' and equally in Arthur Koestler's classic, 'The Sleepwalkers'. Giorgio de Santillana, in his otherwise sympathetic biography of Galileo, characterised as follows the chair at Padua University which he adopted in 1592: 'the chair of "mathematics" then covered the teaching of geometry, astronomy, military engineering, and fortification.'11 Santillana has brazenly omitted a vital traditional role for that post, viz, the teaching to medical students of how to cast a horoscope. That was, after all, how the remedy was found.
There is, in the whole of Santillana's opus, but one reference to the subject, made quite casually: that, late in Galileo's career, a slander was cast against him by the Jesuits, who were then his enemies, averring:
'that Galileo had astrologically predicted the death of the Pope in 1630'12.
This suggests that Galileo enjoyed some renown for his practice of the art. It remains unclear how far that extended: Mirti and Foglia averred that his chart of Cosimo II was 'famous not only in Italy but also abroad, for example in Germany and in Poland'13.
The Stars Compel
The year 1604 was an eventful year for Galileo, with what became known as 'Kepler's star' lighting up in the heavens. He then arrived at his law of falling bodies (that, in equal times, the distance fallen was as the sequence of odd numbers). To that year also belongs Galileo's first, little-known summons by the Inquisition. There was something to which it objected in his chart-readings.
In April of 1604, a young man from the Venice district, who was employed in Galileo's household, made a deposition with the courier archivist of Padua. It was a testimony against Galileo, and comprised three items: that Galileo kept quarreling with his mother (it seems she was objecting to his keeping a mistress plus his three children in Padua); that he was failing to attend mass; and that he was propounding a doctrine of astral determinism to his wealthy clients. No-one could escape the influence of the stars, he was alleged to be claiming, and it was therefore better to know one's own future from a chart-reading. After all, the stars did not lie. After receiving this testimony, the charge formulated by the Inquisition against the astrologer was;
'haver ragionato che le stelle, i pianeti at gl'influssi celesti necessitino'
- he had reasoned that the stars, planets and celestial influences could determine the course of events. The Church was very sensitive on this issue. The charge was not however pursued, since Galileo protected by holding the chair of mathematics at Padua. The Church did not wish to stir up trouble with the university.
This only came to light recently, discovered by the Franciscan Friar Professor Antonio Poppi14. Two sworn denunciations were located in the Venetian state archives in 1990, supporting those found in Padua. At the quattrocentenary celebrations in Padua, the sole astrological note was there struck by Poppi, and his discovery. This stimulated debate amongst Italian academics concerning what this 'dark side' of Galileo, and whether he only did it for the money.
Galileo's lectures on the 'new star' i.e. the galactic supernova of 1604 were very popular, and huge crowds came to hear his view on the matter. Historians never seem to mention what it was he had to say in these lectures. Perhaps this is because his reasoning was rather astrological. The new star, he explained, was born from the conjunction of Jupiter and Saturn, as it appeared next to them. He discussed its qualities by symbolic reasoning concerning the colours ofJupiter and Saturn (the nova was brightly coloured).
A Fatal Mistake
In the year 1609, Her Highness Christina of Lorraine, Duchess of Tuscany, requested Galileo to 'correct' the horoscope of her husband the Grand Duke Ferdinando I, during what proved to be his final illness. By such means one would ascertain his prospects for recovery. By way of comparison, some years earlier, the French Louis XIII in Lyons become greviously ill. Only Morin de Villefranche predicted that he would recover in three months and return to Paris, as duly transpired, as a reward for which Morin was awarded the chair of Mathematics at Paris15. Did Galileo hope to accomplish something similar? Galileo was effectively asked to perform mathematical computations whereby an estimate of length of life could be reached, an unenviable task. He predicted a short recovery and long life, but the Duke died a few weeks later, an event which may not have increased Galileo's confidence in the ancient art.
This is one of the few features of the subject on which science historians have felt at liberty to comment. They have not hesitated to claim that Galileo practiced deception for money. Thus, 'Galileo himself had no more believed when he wrote it [the predicted recovery], than he did when he drew the horoscope of Mergherita Picchena, of Sagredo, or of any of his friends16,' while another has viewed the charts cast as a 'pious fraud.'17 Mirti and Foglia discuss the episode under the severe title, 'Galileo as a Bad Astrologer18' They viewed Galileo as competent on technicalities of chart construction, but shaky on interpretation. He often sought advice from a colleague about chart interpretations, a Mr Brenzoni, where letters from the latter to Galileo remain but those from Galileo are lost.
The Starry Message
In that year 1609, fate had something very different in store for him. It was the time of his Uranus-opposition and saw momentous changes: he acquired a telescope, and left the safety of Padua for Venice. Galileo had practiced astrology during his eighteen years as lecturer in Padua, however after he left for Venice it was no longer politically safe for him to do so19. Soon he was applying his new instrument to the heavens, and in 1610 composed his revolutionary bestseller, Sidereus Nuncius, the 'Message of the Stars'. This short work opened with a memorable account of the qualities of Jupiter:
'So who does not know that clemency, kindness of heart, gentleness of manners, splendour of royal blood, nobleness in public functions, wide extent of influence and power over others, all of which have fixed their common abode and seat in your highness - who, I say, does not know that these qualities, according to the providence of God, from whom all good things do come, emanate from the benign star of Jupiter20'.
This quotation shows that no doubt existed in the mind of Galileo, concerning the attributes of Jupiter, and that he could hardly imagine anyone else doubting such matters. There followed an account of Jupiter's position at the MC of the chart of his patron, Cosimo de Medici, the Duke of Tuscany:
'...Jupiter, which on your Highness's birth had already passed the slow, dull vapours of the horizon and was occupying the Midheaven, from which point it was illuminating the eastern angle, from that sublime throne saw the most happy delivery and all the splendour and magnificence of the newly-born diffused in the most pure air...'
That is, by any standards, a qualitative statement about a time of birth. The Italian Orientalemque angulum sua Regia illustrans can be translated as 'illuminating the Eastern angle of which he [Jupiter] is the ruler': it refers to Cosimo de Medici's rising sign ('orient') of Sagittarius, as being ruled by Jupiter. Such a comment, on the opening pages, is reminiscient of a similar remark in another classic of modern science: Kepler's Astronomia Nova of 1609 likewise opens discussing the position of Mars as the 'Master of the Horoscope' of the Emperor Rudolf II. Galileo further gives his view of how astrology works, at the crucial birth-moment:
' ... in order that your tender body and your mind might imbibe with their first breath that universal influence and power, alluding to the condition of the horoscope at that instant, as dominated by the planet Jupiter.
The book was dedicated to Cosimo Medici, and concerned the moons of Jupiter. This was a political strategy, as, to quote Santillana, 'Once the House of Medici had accepted the dedication, it became mandatory for them to exist21.' Magini, the professor of astronomy at Bologna, fiercely opposed Galileo and affirmed that the new planets were to be 'extirpated from the sky.' As the book was proposing that the new Moons of Jupiter should be named after him, the 'Medician stars,' clearly his chart was relevant. Its purpose was to establish that the Duke's chart did indeed have such characteristics as he had claimed22. Thereby Galileo was able to gain the top job of court philosopher to the Medicis in Florence.
The Medici grand dukes had deliberately modelled themselves upon absolute-monarch kingly images, so that Galileo's hyperbole about 'splendour of royal blood' did not seem inappropriate. The young Cosimo had three brothers, so that the four new stars were shared out, one to each. It was no mere coincidence, as Galileo explained in his dedication of Sidereus Nuncius to the young Cosimo, that 'bright stars offer[ed] themselves in the heavens' immediately following his enthronenent: the four stars had been 'reserved' for the Medicis. The Nuncius dedication was a political use of astrological symbolism.
Heart of the Universe
As one of the first Copernicans, Galileo viewed the Sun as stationary and at the centre of things. A letter of his to Dini described it as being the heart of the solar system:
'...so that it is rather like the heart of an animal in which there is a continual regeneration of the vital spirits, which sustain and give life to all the bodies which surround it.'
(23 March 1615)
This letter showed "the translation into astrological language of the 'strengthening' of rays according to where they meet, and of their intersection, fragmentation and augmentation..."23
Charts for his Daughters
Galileo drew up charts and interpretations for his two daughters, Virginia and Livia, which still remain. In 1613, when they were 13 and 12 years respectively, he placed them in a monastery for life, as they were too expensive to maintain. The first monastery he approached refused, on the grounds that they were too young, so he found another! They remained devoted to their famous father.
These written-out character interpretations may suggest that Galileo had already resolved to send his daughters to a monastery. Mirti was not over-impressed by them, averring that, while Galileo had portrayed Virginia as 'solitary, silent, taken up with her concerns', her horoscope rather showed 'an enthusiastic Leo, serious and understanding of human suffering'. Contrariwise, a journalist in 'La Stampa' extolled the insight of these interpretations as 'almost prophetic.' These chart interpretations by Galileo emphasise the qualities of the fixed star Spica. A recent 600-page book all about Galileo's relationship with his daughters24 makes no allusion to these character-interpretations, as shows how highly censored the subject remains.
The Warning
On Thursday, 25 February 1616, the file of the Inquisition at Rome recorded:
'the censure passed by the theologians upon the propositions of Galileo - to the effect that the Sun is the centre of the world .. if he (Galileo) do not acquiesce therein, he is to be imprisoned.' 25
This was Galileo's first solemn warning. It came over Galileo's birthday (15th or 16th of February Old Style), ie he was experiencing a solar return, as if the Sun were siding with him on the matter!
Sagredo and Salviati
Galileo's classic work, 'Dialogues between Two World-Systems' was published in 1632, as a discussion between three characters, Sagredo, Salviati and Simplicius. Salviati and Sagredo were real persons, and had been Galileo's closest friends. They had both tragically died young - 'in the very meridian of their years', as Galileo put it. This was explained to me by an Italian, who also added that it would be a mistake to regard the third figure, Simplicius, as merely the dense Aristotelian: he often functioned as the voice of straightforward common-sense, stopping Salviati (Galileo's chief mouthpiece) from going too far.
The Dialogues were cast as having been at 'the palace of Sagredo' in Venice, and Sagredo was characterised as 'a man of noble extraction and trenchant wit.' The real-life Guiseppe Sagredo had been accustomed to consult Galileo for astrological guidance. Details remain of the considerable effort which Galileo put into composing 'primary directions' enabling him to comment upon how Sagredo's life was unfolding. These 'directions' had a sidereal emphasis, using the fixed stars Caput Medusa, Rigel Bellatrix, Hercul., Procyon, Regulus, Vindemiatrix, Spica and Arcturus. His commentary on Sagredo's horoscope referred to the Pleiades:
'The ascendent falls in the Terms of Venus in her own house, surrounded by the fixed Pleiades and applying to Jupiter by an exact sextile. She is free from rays malefic to herself.'
A letter from Sagredo to Galileo requested a chart reading for a colleague, in a manner which, Mirti found, 'suggests constant, similar requests'. Galileo's synastry with Sagredo was: Sun trine Sun (1°), appropriate for discussions on whether the Sun moved, and Saturn square Saturn (15')26 appropriate for the establishing of modern science.
Favaro, in his essay of 1881, claimed that in these Dialogues, Salviati, as Galileo's mouthpiece, was 'making fun of genethliacal astrology'. He thereby implied that Galileo's belief in astrology had vanished in his mature years. There is only one passage to which this claim of Favaro could refer, to which we now turn. On the Fourth Day of the 'Dialogue', published in 1632, a fallacious argument was introduced to demonstrate the motion of the Earth, concerning the tides. Though wholly mistaken, it was perceived by Galileo as having a crucial importance. He wanted to have the tides mentioned in the title of the book, and was only with difficulty talked out of it27. His argument involved rejecting what seemed evident to many people, viz. that the Moon affected the tides. After outlining the theory, Salviati added, shockingly:
'But among all the great men who have philosophised about this remarkable effect, I am more astonished at Kepler than at any other. Despite his open and acute mind, and though he has at his fingertips the motions attributed to the earth, he has nevertheless lent his ear and his assent to the moon's dominion over the waters, to occult properties, and to such puerilities.'
There is a margin entry, 'Kepler respectfully rebuked.' Neither 'Sagrego' or 'Simplicus' were able to make much sense of the argument, with the former commenting: 'This matter, for a full understanding of which I need a longer and more concentrated application of my mind, is still obscure to me...' while 'Simplicius' added: 'as for the discussions we have had, and especially the last one about the explanation of the tides, I really do not understand them completely.'28
Contrary to Favaro's opinion, and all those who have alluded to it since, the Dialogues do not in fact allude to astrology. Salviati, in the above passage, has merely claimed that 'occult properties' are an inadequate explation for the motions of the tides. Action at a distance was problematic, and Galileo was groping towards some more mechanical explanation.
Is there any other passage to which Favaro's allegation could have referred? Mr. Shea has averred that a passage in the Third Day of the Dialogue 'provides Galileo with the opportunity of distinguishing the Pythagoreanism of the mathematicans from that of the astrologers and the alchemists29', as follows:
Simplicius: 'I know very well that the Pythagoreans held the science of numbers in high esteem, and that Plato himself admired the human intellect and considered it to partake of divinity simply because it understood the nature of numbers. I would not be far from making the same judgement myself. But I do not believe that the mysteries which caused Pythagoras and his school to have such a veneration for the science of numbers are the follies that abound in the sayings and the writings of the common man.'
We here learn that Simplicius has a Pythagorean bent, but that is all. The doctrines of Pythagoras formed a backbone for astrological rationale, not least for Galileo's contemporary Kepler. Some antithesis between 'mystery' and 'folly' appears in this statement, but the meaning attributed to it by Shea is quite absent.
A Waning Belief?
In the prime of his life, Galileo believed in astrology. Two items of evidence place this matter beyond reasonable doubt: one is his statement in Sidereus Nuncius, and the other is the fact that his close friend Sagredo was accustomed to consult him over 'primary directions' ie advice on the course of his life. Sagredo was a spokesmen for the new philosophy in the 'Dialogues.' The last existing horoscope by Galileo was dated for the year 1625, when he was over sixty. This is the latest for which we have evidence that he constructed a horoscope. Concerning his belief in later years, it seems that we have evidence only for a note of irony being sounded.
A letter of Galileo's from 1633, the year after his 'Dialogue Concerning Two World-Systems' was published, to his patron Diodati, alludes to Morin de Villefranche, Mathematics professor at Paris and one of the best-known astrologers of his day:
'I am astounded that Morino has such an extremely high regard for judicial [astrology] and that he claims with his conjectures (which to me appear uncertain, if not very uncertain) to establish the certainty of astrology; and it would really be a wonderful thing if - as he promises - he can, shrewd as he is, place astrology in the highest position of the human sciences; and I shall wait with great curiosity to see this marvellous innovation30.'
Favaro commented, 'In these words we do not find the sense of absolute reproach, as others are pleased to find in them'. Galileo was here casting doubt on whether astrology should be viewed as a science: traditionally, from Ptolemy's Tetrabiblos, it was regarded as an art, astronomy being the associated science.
Judgement Passed
On 22 June, 1633, Galileo was found guilty by the Roman Catholic Church for teaching that the Earth moved, and imprisoned for life. On this ruinous day, whose shadow reached with such grave consequence into future centuries, the two malefics Mars and Saturn stood in exact opposition (2' orb), with Mars conjunct Galileo's own Mars (1°).
Comments on the Tetrabiblos
The contents of Galileo's library were classified by Favaro. His section 6 was called, 'Astrology and Occult Philosophy'. There were about fourteen books in this section on or related to astrology31, including an annotated Tetrabiblos. These notes by Galileo upon Ptolemy could throw light upon the manner and extent of his belief in the subject. From Favaro's classification we may cite:
