We have taken a cursory view of the different steps in Râja-Yoga, except the finer ones, the training in concentration, which is the goal to which Raja-Yoga will lead us. We see, as human beings, that all our knowledge which is called rational is referred to consciousness. My consciousness of this table, and of your presence, makes me know that the table and you are here. At the same time, there is a very great part of my existence of which I am not conscious. All the different organs inside the body, the different parts of the brain — nobody is conscious of these.