When once the mind is disciplined by concentration, by the power of will then the mind becomes your servant. Once the mind has become your servant, then what more can you wish? Then your world is your own, you are the king of your kingdom. No doubt, one might say: "Why should we not let the mind be free also, as we are free?" But we and the mind are not two beings. It is like saying: "Let the horse be free and the rider be free." Then the horse wants to go to the south and the rider wants to go to the north. How can they go together?