See Physical and Psychological Faces for the formative development of the zodiac.
The signs -- "auts" -- of the zodiac are active environments for the impersonal energies of the planets, which focus the cosmic energies through our psyches; they must be read in their structural-semantic or formative equations to understand their function and inner qualities.
Each sign shows a particular relationship of Aleph and Tav, and the zodiac must be read in different directions according to the evolution and involution of material and psychological structure. In its linear development, the zodiac begins when Hay, life, the fifth letter of the Hebrew alphabet, forms Toleh/Aries, and continues through Betolah/Virgo, where Yod gives it existence. Only with the seventh sign, Mozenaim/Libra, is objective existence achieved. 'Aaqarav/Scorpio, formed by the existential 50 life/death of Nun offers the wisdom of Chokmah to those who learned how to listen in Libra. Tav reaches its destination in Sagittarius, where material development is perfected in the rainbow of Qoshet and psychological maturity stands across the threshold, in signs which do not put obstacles in the way of its realization (70) and represent states of perfected femininity (90) and masculinity (100).
Energy begins its journey of structuration with Toleh/Aries, where the cell is formed, and builds its foundation in the future with the first four signs of the Zodiac. All these energies -- the "autiot of zodiac" ("sign" is "aut" in Hebrew) must be read in their structural/semantic equations, from Toleh to Daghim. They describe the inter-relationship and structural development of two intertwined energies: the interior energy of life/death, Aleph, and the exterior energy of existence, Yod. According to the equation, these two energies develop in evolutionary or involutionary directions.
Four diagonals connect the future/material structuration with the past/psychological development. After the foundation, physical energy is concentrated in the Northern Face: Tayt/9 (the perfected cell of Toleh) which forms Leo and gains existence as the seed of Yod/10. The perfected projections of these two states, the upper and lower diagonals of the Southern Face, are Tsadde/90, perfected womanhood, and Qof/100, perfected manhood.
Having gained actual existence (Yod/10 forms Virgo), energy can enter into objective reality with the seventh sign, Libra/Mozenanim, which is formed by Lammed/30. To recall, the signs begin with 5/Life and progress 5-6-7-8-9-10 before jumping to 30/Organic (equilibrating) movement. On the Western face, we encounter action, existential life and material perfection before coming to the choice of psychological death and rebirth at Capricorn/Ghedi. Note that Libra/Mozenaim, West-South, is the first diagonal lit by Sun/Hamah in the West.