other you may try from time to time when you find a sufficient quietude. Concentration there leads – or should lead – to the psychic opening.Sri Aurobindo
Letters of Sri Aurobindo
Volume II - Part 2
Fragment ID: 11647
It [concentration in the heart] is the best to “start with” – but as you have already started with success on the two higher centres, there is no reason why you should discontinue that. The other you may try from time to time when you find a sufficient quietude. Concentration there leads – or should lead – to the psychic opening.