The meaning of the symbols

Sri Aurobindo's Symbol
The descending triangle represents Sat-Chit-Ananda. The ascending triangle represents the aspiring answer from matter in the form of life, light and love.
The junction of both, the central square, is the perfect manifestation having at its center the Avatar of the Supreme which is symbolised by the lotus. the water inside the square represents the multiplicity, the creation.

The Mother's Symbol
The central circle represents the Divine Consciousness. The four petals represent the four powers of the Mother - Wisdom, Strength, Harmony and Perfection. The twelve petals represent the twelve powers of the Mother manifested for Her work.