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Mercury- Astrology's Natural Significator, by Garry Phillipson

Modern texts often refer to Uranus as the planet that governs astrology and astrologers. But tradition tells a different story, revering Mercury as the symbol of occult knowledge that bridges the material and spiritual worlds. Garry Phillipson comments on why he sees Mercury as the perfect significator for an art that is shaped by, and expresses itself through, the intermediary influence of the astrologer's judgement.

Early in the first century CE, Marcus Manilius wrote "You, God of Cyllene [Mercury], are the first founder of this great and holy science [astrology/astronomy]; through you has man gained a deeper knowledge of the sky - the constellations, the names and courses of the signs, their importance and influences...." [1]

Though dissenting voices have been raised - particularly in modern times, when Uranus has frequently been put forward as the ruler of astrologers and astrology[2] - the weight of astrological tradition is on the side of Mercury.[3] The implications of Mercury's rulership of our subject are what I'd like to look at here.

Mercury is, by nature, ambivalent, difficult to see, neither one thing nor the other. As William Lilly says: "We may not call him either masculine or feminine, for his is either the one or the other as joined any planet; for in conjunction with a masculine Planet, he becomes masculine; if with a feminine, then feminine ... with the good he is good, with the evil planets ill".[4] So the planet of astrology and astrologers does not suggest that this study should be clear and obvious to all; rather, it is elusive by its very nature.

If the subject is elusive in the way just described, that accounts very neatly for why the scope and precision of astrology fail to be revealed by tests and research. But this still leaves a question: If astrology is such an elusive thing, how can it be that so many astrologers manage to use it? What could render such mutability manageable? What does the astrologer do, to see meaningful signs in this quicksilver study? How can the fact that different astrologers use different, sometimes conflicting, techniques be reconciled with the fact that they all claim to get accurate results?

As far as I can see, there are only two basic ways of thinking about this. One is to insist that there is one ultimate astrological technique - it's just taking us a while to figure out what it is. This was the approach of John Gadbury when he complained that "we have not yet that science perfect" and started gathering especially accurate data to work with, in the hope of arriving once and for all at a definitive, perfected, body of astrological technique.[5] The problem with this belief is that there is no evidence to support it. Although astrology has been around for millennia, astrologers today work with as wide a range of differing techniques as ever.

The alternative perspective - which I believe fits better with the symbolism of Mercury - is to suggest that, in some way, different astrological techniques can work equally well. Just as Mercury will take on (for instance) the qualities of Venus or Jupiter when it is aspected by them, so astrology, chameleon-like, can assume the guise of (for example) either Western or Vedic techniques.

The essence of astrology is interconnection; the interconnection between planets in the sky and experience in the human realm. Given this, it seems only reasonable that interconnection should be an important part of what we see when we look at astrology. Just suppose, for a moment, that astrology was equally effective whether we were asking a life-changing question in a consultation or a question picked at random in a test. Under those circumstances - if it worked regardless of our attitude toward it - astrology in itself would not display interconnectivity.

We would have astrology saying that there is a profound level of interconnection between the planets and human experience; and yet astrology itself would be impervious to this interconnection. This seems close to self-contradiction. Surely we would expect the process of reading an astrological chart to epitomise the principle of interconnection upon which the entire subject is based, rather than being somehow exempt from it. When you really look at it, I'd suggest the idea of an astrology which can work at its optimum, regardless of the mental state of the astrologer, is a contradiction in terms - comparable to the idea of water which does not display wetness.

It is, therefore, consistent with the nature of astrology that it cannot be conclusively validated in objective, scientific terms. But imagine the converse - that astrology could be conclusively disproved within a scientific frame of reference. This, again, would not fit with the ambiguous nature of Mercury.

So if we agree that Mercury's qualities are also the qualities of astrology, it is entirely consistent that scientific research into astrology should, from time to time, throw up a glimmer of something, the hint of an astrological effect which cannot be explained out of existence - studies such as the Gauquelin work[6] and perhaps the time-twin research of Roberts and Greengrass.[7]

I find it interesting to consider the symbolically rich outcome of one of the first attempts to apply statistical science to astrology. (It was statistically insignificant - but the way in which the test arrived at this insignificance is, in itself, the source of the symbolic richness.) In the early 1950s, Carl Jung conducted a statistical study of the synastry between married couples. He had the idea, based on a reading of Ptolemy, that three inter-aspect combinations might be present at a level above chance: Sun conjunct Moon, Moon conjunct Moon, and Ascendant conjunct Moon. Analysing the data in three batches (as it came in), Jung found a high level of significance each time - but each of the three groups showed a different one of the planetary combinations he was looking for. When the three groups were merged together, the appearance of significance which was present in each individual group disappeared.[8]

Now, consider the suspicions which Jung began to entertain when he was halfway through the tests and getting the results he expected to get: "The thought struck him: Had Mercurius ... played a trick on him?" [9]

When Jung wrote about the experiment, he repeatedly drew a parallel between his findings and those of J. B. Rhine in parapsychology tests:

"One consistent experience in all these experiments is the fact that the number of hits scored tends to sink after the first attempt, and the results then become negative. But if, for some inner or outer reason, there is a freshening of interest on the subject's part, the score rises again. Lack of interest and boredom are negative factors; enthusiasm, positive expectation, hope, and belief in the possibility of ESP make for good results and seem to be the real conditions which determine whether there are going to be any results at all. In this connection it is interesting to note that the well-known English medium, Mrs Eileen J. Garrett, achieved bad results in the Rhine experiments because, as she herself admits, she was unable to summon up any feeling for the 'soulless' test-cards." [10]

This is - to say the least of it - consistent with the idea that belief, or commitment, is required of astrologer and client. Astrology, and the astrologer, wax eloquent or fall dumb; speak unbelievable truth or banal falsehood; and all depends on the sum total of the factors in play. Amongst those factors, belief in astrology will create an interested, charged emotional state, helping create the right conditions for an accurate, useful reading. So that those who believe tend to find their belief vindicated; those who doubt find good reason to doubt. Mercurius's finest trick is to convince us each to wrap ourselves, ever tighter, in a world of our own imagining.

Notes & References:

  1] Manilius, Astronomica, trans. G. P. Goold, Cambridge, MA: Harvard University Press, 1977/1997, p. 7 (1 16-37).
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  2] This (amongst much else) is discussed on the Skyscript Forum: where Kim Farnell reports that Raphael, in 1879, is the first astrologer she has found who described Uranus as the ruler of his subject.
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  3] E.g. Al-Biruni, The Book of Instruction in the Elements of the Art of Astrology, London: Luzac, 1934 (facsimile reprinted by Ascella Publications (undated), p. 254; and many subsequent sources including Gadbury, Lilly and Partridge.
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  4] 51. William Lilly (1647), Christian Astrology, Nottingham, U.K.: Ascella, 1999, p. 77.
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  5] Patrick Curry, Prophecy and Power, Oxford, England: Polity Press, 1989, p. 73.
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  6] The best summary of this work is probably still: Suitbert Ertel and Kenneth Irving, The Tenacious Mars Effect, London: Urania Trust, 1996.
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  7] Peter Roberts and Helen Greengrass, The Astrology of Time Twins, Durham, UK: Pentland Press, 1994.
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  8] Maggie Hyde, Jung and Astrology, London: Aquarian Press, 1992, pp. 130-132. This is a wonderful and highly-recommended book; (the chapter on synchronicity detailing Jung's study is reproduced on this site at
For Jung's account, see C. G. Jung, Synchronicity: An Acausal Connecting Principle, London: Routledge & Kegan Paul, 1972. The paper, with the appendix On Synchronicity is at p.417-531 of Vol 8 of the Collected Works. Note that Jung organised a follow-up analysis of the data, which again suggested an unconscious complicity between researcher and data.
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  9] Marie Louise von Franz, C. G. Jung: His Myth in Our Time, London: Hodder & Stoughton, 1975, p. 238. Cited in Hyde, Jung and Astrology, p. 130.
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  10] Collected Works Vol 8 p.434; Para 838.
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Garry PhillipsonGarry Phillipson has practised astrology since 1976. His other interests include Buddhism and Advaita Vedanta. Astrology in the Year Zero published in 2000, resulted from Garry's study of astrology - in particular, from his investigation of the philosophy and assumptions that underpin the subject. His articles and lectures have appeared under the aegis of groups including the Astrological Association of Great Britain, the Astrological Lodge, the Company of Astrologers, the Urania Trust, the Standing Conference on Organizational Symbolism, The Mountain Astrologer, and Ascella. He is currently working on a PhD about astrology and truth at the University of Wales, Trinity St. David.

Visit Garry's website at

© Garry Phillipson, May 2004

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