Development of the discriminating mind
This is the first half of the zodiac, symbolising the development of the coherent personality through ordinary life, and this triangle influences the development of the discriminating mind during the round of personal experience.
After the reversal of the wheel (when the growth process is undergone by progressing through the signs from Aries through Taurus to Pisces) the accumulation of the experiences of personal life culminate in the balance point of Libra, where personal and spiritual awareness become equal influences on the individual, and the growth process begins in earnest at the first initiation. During this period of reversal:
Gemini and Libra are the two strictly human signs; they are the signs of the ordinary [individual]. Gemini upon the Mutable Cross stands for [our] humanity, whilst Libra upon the Cardinal Cross rules [our] subjective and spiritual life […] The emphasis… on Gemini and Libra as far as humanity is concerned is on human attainment and achieving the point of balance before the other attainments become possible. (EA 242-3)
After reversal, following the struggle outlined below, these signs work in a specific way towards that crucial stage “wherein there is increasing response to the energies, concealed by the rising sign. They evoke the unexpected and produce the hastening of the evolutionary process and the unfoldment of the inner life.” (EA 52, emphasis added) Specifically, the one fire and two air signs focus on the development wherein:
the mental principle [Aries], the discriminating mind [Gemini, Libra], is developed and in this specific connection (not in a general connection) the emphasis is laid upon the influence of Aries, Gemini and Libra. Under that influence the [individual] learns to overcome desire through experimentation with and experience of every kind of desire and selfish impulse. Thus gradually, and with infinite pain, the human soul learns to function first as a member of the human family, and, secondly as a spiritual entity, the divine soul. (EA 52)
Esoteric Astrology: 52, 242