" When meditation becomes very deep, breathing becomes slow, steady, and even, and the windows of the senses close to all outward sensations. Next the faculties of the mind quiet down, resting from their usually frantic activity; even the primal emotions of desire, fear, and anger subside. When all these sensory and emotional tides have ceased to flow, then the spirit is free, mukta – at least for the time being. It has entered the state called samadhi. Samadhi "

― Krishna-Dwaipayana Vyasa , The Bhagavad Gita