When one has succeeded in making this Samyama, all powers come under his control. This is the great instrument of the Yogi. The objects of knowledge are infinite, and they are divided into the gross, grosser, grossest and the fine, finer, finest and so on. This Samyama should be first applied to gross things, and when you begin to get knowledge of this gross, slowly, by stages, it should be brought to finer things.