The nature of the mind is flickering and unsteady. But a self-realized yogi has to control the mind; the mind should not control him. One who controls the mind (and therefore the senses as well) is called gosvami, or svami, and one who is controlled by the mind is called godasa, or the servant of the senses. A gosvami knows the standard of sense happiness. In transcendental sense happiness, the senses are engaged in the service of Hrsikesa or the supreme owner of the senses—Krsna. Serving Krsna with purified senses is called Krsna consciousness. That is the way of bringing the senses under full control. What is more, that is the highest perfection of yoga practice.