The force of desire acting in the psychic Prana, the vital being that links the physical body with the mental being, prevents the pure working of the mental (or higher) force through the individual and out into the world. This is not just the craving of the vital being directly, but also affects the more subtle forms of the vital nature, such as the emotional mind and the active mind associated with sensations and actions. There are tight links between all these elements of the inner being. Sri Aurobindo explains: “The deformation of the emotional mind hinges upon the duality of liking and dislking, raga-dvesa, emotional attraction and repulsion. All the complexity of our emotions and their tyranny over the soul arise from the habitual responses of the soul of desire in the emotions and sensations to these attractions and repulsions. Love and hatred, hope and fear, grief and joy all have their founts in this one source. We like, love, welcome, hope for, joy in whatever our nature, the first habit of our being, or else a formed (often perverse) habit, the second nature of our being, presents to the mind as pleasant, priyam; we hate, dislike, fear, have repulsion from or grief of whatever it presents to us as unpleasant, apriyam. This habit of the emotional nature gets into the way of the intelligent will and makes it often a helpless slave of the emotional being or at least prevents it from exercising a free judgment and government of the nature.”
“By getting rid of desire in the psychic Prana and its intermiscence in the emotional mind, we facilitate the correction. For then attachment, which is the strong bond of the heart, falls away from the heart-strings; the involuntary habit of raga-dvesa remains, but, not being made obstinate by attachment, it can be dealt with more easily by the will and the intelligence. The restless heart can be conquered and get rid of the habit of attraction and repulsion.”
Briefly, then, Sri Aurobindo provides a direction for overcoming the force of desire which then opens the door for a higher action to use the human instrument in a purer and more direct way.
Sri Aurobindo, The Synthesis of Yoga, Part Four: The Yoga of Self-Perfection, Chapter 6, Purification–the Lower Mentality, pp. 632-633