The following table shows the relationship between the enneagram types, planets and signs. The last column shows the corresponding chakras, the 7 energy centers along the human spine, which in alchemical tradition are aligned with the planets in the same order. I have also added Uranus and Neptune to this order.


Enneagram Type Planet Ruling Signs Exalted Planets chakra
One Mercury Virgo, Gemini Mercury in Virgo 5
Two Moon Cancer Jupiter 6
Three Sun Leo Neptune 7
Four Neptune Pisces Venus 6
Five Uranus Aquarius Mercury (strong) 7
Six Saturn Capricorn, Aquarius Mars in Capricorn 1
Seven Jupiter Sagittarius, Pisces Venus in Pisces 2
Eight Mars Scorpio, Aries Sun in Aries 3
Nine Venus Libra, Taurus Saturn in Libra, Moon in Taurus 4

As you can see (if you know a little astronomy), the sequence of the Ennneagram Types corresponds to the positions of the planets in their orbit around the Sun. The Sun and Moon are the archetypal pair, the Father and Mother principle. They correspond to Types Three and Two respectively. From there, if you count backwards from Type One (Mercury), to Type Nine (Venus), Type Eight (Mars) and so on out to Neptune (Type Four), the types line up exactly with the planets as you move out from the Sun. You can also count forward from Neptune and Type Four, and the planets correspond in order as you go inward to the Sun and Moon. As you can see from the table, these positions of the planets are also related to the sequence in the zodiac of the signs they rule.
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