Illumination arises from the Self. Ramani Maharshi

Illumination arises from the heart (the Self) and reaches the brain, which is the seat of the mind. If the mind is turned inwards towards the source of illumination, objective knowledge ceases, and the Self alone shines as the heart. p. 32

Heart is another name for the Self. p. 33

In the center of the cavity of the Heart, the sole Brahman shines as Atman. It is both inside and outside and has neither an inside nor an outside.

That which is the sources of all. what in which all live, and that into which all finally merge, is the heart.

Concentrating on the Heart is the same as concentrating on the Self.

After the Rain, Silent Encounters with Sri Ramani Maharshi, purchased at Hridaya Yoga, France, Published in India.