The Secret Doctrine of Goddess Lalita
(Sri LalitaAṣṭottara Rahasyārthamu)
7. svaprakāśā
She who is self-luminous.
An object exists only if it is known to a cognizing intelligence. This is true in the phenomenal realm, but not true in the realm of śakti, since śakti is not an object. śakti is Consciousness, the subject that knows all objects. When the subject is Consciousness itself, there is no need for another entity to vouch for its existence. Consciousness is Self-evident. While the whole world is known to Consciousness, Consciousness knows Itself through the ever-present “I Am” awareness. Because It is aware of Its own Beingness, śakti is svaprakāśā, self-luminous. No doer-ship or activity can be attributed to It. Unlike fire which is inert and unaware of its own nature (its ability to burn other things), śakti is the Supreme Power of the Supreme Consciousness, so It is Self-Evident and Self-Luminous.
Hence, śakti is both the subject and the object. She is apramēyā because She is the subject and cannot be known through any means of knowledge. Since She is svaprakāśā, She knows Herself through Herself.