But this science deals with the mind, which moves all the time; the moment you want to study it, it slips. Now the mind is in one mood, the next moment, perhaps, it is different, changing, changing all the time. In the midst of all this change it has to be studied, understood, grasped, and controlled. How much more difficult, then, is this science! It requires rigorous training. People ask me why I do not give them practical lessons. Why, it is no joke. I stand upon this platform talking to you and you go home and find no benefit; nor do I. Then you say, "It is all bosh." It is because you wanted to make a bosh of it.
I know very little of this science, but the little that I gained I worked for thirty years of my life, and for six years I have been telling people the little that I know. It took me thirty years to learn it; thirty years of hard struggle. Sometimes I worked at it twenty hours during the twenty-four; sometimes I slept only one hour in the night; sometimes I worked whole nights; sometimes I lived in places where there was hardly a sound, hardly a breath; sometimes I had to live in caves. Think of that. And yet I know little or nothing; I have barely touched the hem of the garment of this science. But I can understand that it is true and vast and wonderful.
- Swami Vivekananda
THE POWERS OF THE MIND ( Delivered at Los Angeles, California, January 8, 1900 ) The Complete Works of Swami Vivekananda/Volume 2