The tiny hole in the Heart is opened by vichara with the result that ‘I-I’ consciousness shines forth.

Devotee:  There arose a doubt if ‘I-I’ consciousness be the same as nirvikalpa samadhi or anything anterior to it.

Ramana Maharishi:  The tiny hole in the Heart remains always closed, but it is opened by vichara with the result that ‘I-I’ consciousness shines forth. It is the same as samadhi.