Re: The Zodiac in Leonardo Da Vinci's Last Supper
Thanks Interbane. The Last Supper aims to connect the deepest realities of human life. In terms of Christianity, the story says the deepest reality is that when a man, Jesus Christ, showed the world how to connect time with eternity, the response was betrayal and execution. The painting is set at the dramatic moment of betrayal, with Judas holding his bag of money and appearing surprised at the statement by Christ that one of the twelve will betray him.
In astronomy, the deepest reality affecting human life, and especially from the limited visual perspective available in Leonardo’s day before the telescope, is the annual cycle of the seasons. The painting uses the very old and widespread Christian motif of saying that the story of Jesus Christ reflects the annual cycle of the seasons, seen in the path of the sun through the stars.
Your question is then how Leonardo did this technically, using stars for body shapes. It is not a matter of using hands or face as anchor points. Rather, Leonardo first looked at the sky, drew the shape of the solar stars of each month using the precise natural accuracy for which he was rightly famous, and then embedded that natural observation in its sequential place in the painting.
His objectives were to use this traditional matching of apostles and months (as seen at Chartres Cathedral, Amiens Cathedral, St Denis Cathedral, etc etc) as the lightly concealed structural framework upon which the dramatic story of betrayal could be built. So there is not a simple anchor rule.
From right to left, the star path of the sun is seen as follows in the depiction of the twelve apostles of the Last Supper. Note that the video
provides the star groups in reverse (from left to right starting with Pisces). The list below uses the star groups from right to left in correct order of time, beginning with Aries and going through the course of the year.
1. Hands and forearms
2. Hands (but small error in video where Max did not recognise the left hand is modelled on the Pleiades)
3. Arms and hands (possibly also head)
4. Head, body and arms
5. Hands and arms
7. Head, body and arms
8. Hand, head, body, arm, hand, dagger
9. Head and arms
10. Head and hands
11. Head, body and arms
12. Shoulder brooch, arms and hands
And Jesus Christ as the central focus of the painting is modelled on the stars of the constellation Pisces, marking the position where the spring equinox precessed in 21 AD, with head, arms and hands. Leonardo also used this same stellar framework of the two fishes for his depiction of Christ in his painting of the Baptism of Christ.
You have asked, Interbane, if the use of the hand of Doubting Thomas is an anomaly in the overall pattern. As the list above reflects, the stars of each constellation are unique in apparent shape, and each is very different and distinct. Only six of the twelve include the head of the figure in the depiction of the star group, while in the other six the stars are just used for hands and/or arms.
Thomas is pointing his index finger straight up at the zenith of the sky, in a traditional philosophical symbol of heaven, used by other painters such as Raphael in his School of Athens completed soon after The Last Supper. Raphael has Plato pointing up to symbolise universal eternity and Aristotle pointing down to symbolise particular time. A quite interesting recent comparative discussion is at http://www.advocateenterprise.org/leonardo.html
Now, the fact is that the main star group of Virgo, the sixth constellation, is similar in shape to a pointing hand. None of the other constellations form this shape. For Leonardo, with his intense anatomical interests, this presents a basic opportunity to use the hand shape, and also to encode the basic message of the painting.
The message is that the pointing finger invites the viewer to actually look up at the cosmos, to see the grandeur of the natural universe revealed in the visible shape of the stars of the night sky, and to reflect on how the story of Christ incarnates in human form the real and constant eternal pattern of nature formed by the path of the sun through the stars.