Involution: the inverse movement from Spirit to matter, which preceded evolution. Spirit “involves” itself in matter, and takes on layer after layer of “material” bodies until it reaches the Nadir of existence in the material plane. From that moment on (evolution occurs), Spirit moves upwards again, transcending (evolving through) layer after layer, untill it returns to it’s point of departure in the Divine.(see also here)
Through the concept of “involution and evolution” we can hold both a.) the truth of the limited bodymind (ego) as separate from Divinity and b.) the truth of individual interconnectedness with the Divine such that we are, consciously or unconsciously, a Face of the Divine.
The Involution-Evolution Arc (quoted from this page)
The yin-yang diagram shows reality as a circle. The Involution-Evolution Arc in contrast is linear (although it can also form a circle (left). Spirit descends or falls into Matter, then ascends back to Spirit. This basic cosmological principle is found in Samkhya and Kashmir Shaivism among the Indian philosophies, and Christianity, Gnosticism, Manichaeism, Neoplatonism, Sufism and Kabbalah in the Middle Eastern and Western systems of thought. In the 19th and early 20th centuries it was represented by the Theosophy of Blavatsky, the Anthroposphy of Steiner, the Integral Yoga of Sri Aurobindo, and the teachings of Meher Baba. These are all metaphysical systems of thought. However the inventor and philosophy Arthur Young proposed a scientific version which illustrates stages in terms of increasing degrees of restriction or freedom (very much like Gurdjieff’s cosmology in this regard)
The Involution and Evollution Arc according to Arthur M YoungIf we have (following the mandala and tetrakys models) four planes of existence altogether, then the descending-ascending principle passes through seven evolutionary stages altogether (3 descending, 1 at the bottom, and 3 ascending). Seven is another one of those fundamental numbers, but more so in esotericism and metaphysics than in mathematics or science (although Arthur Young does present philosophical arguments for the validity of the seven). Thus seven planets, metals, celestial spheres etc in ancient Mithraism and Chaldeism, seven chakras (subtle organs of consciousness) in Shakta Tantra, forty-nine (7 x 7) days of intermediate (between death and rebirth) existence in the Tibetan Book of the Dead, seven levels on the Kabbalistic Tree of Life, seven planes, cycles, root races, subtle bodies, etc in Theosophy, and so on.