Question: Why should Self-enquiry alone be considered the direct path to Realization?
Bhagavan: Because every kind of path except Self-enquiry presupposes the retention of the mind as the instrument for following it, and cannot be followed without the mind. The ego may take different and more subtle forms at different stages of one's practice but it is never destroyed. The attempt to destroy the ego or the mind by methods other than Self-enquiry is like a thief turning policeman to catch the thief that is himself. Self enquiry alone can reveal the truth that neither the ego nor the mind really exists and enable one to realize the pure, undifferentiated Being of the Self or the Absolute. ~ Ramana Maharshi