Dhyana

Almost each one tested the fact that when one starts to concentrate his spirit on any immediate object or an idea, the spirit starts to wander. It is very difficult to maintain the spirit occupied with a simple thought. The ancient sages also encountered the same problems. Arjuna, in Gita had mentioned that the control of the spirit is an impossible thing on ground. Consequently, it was advised by Krishna that although the ordering of spirit is difficult, it can be made quiet and regular by the regular practice of the vairagya and of the abhyasa. However, he informed that yoga is very difficult for the people whose spirits regular and are not ordered. Pantanjali, in Sutra yoga underlined these two qualities to carry out the ordering of spirit. Consequently, in fact same qualities make the gasoline of yoga.
The spirit is like a pond disturbed with many impurities. Initially you must stop the contribution of the fresh impurities and then to remove the existing impurities to clean the spirit. Abhyasa is one of the practices to purify the spirit. Dhyana is one of the secondary practices of the abhyasa. It is a stage which a person reaches after having practised the concentration during some time. At the beginning of the dhyana, the spirit is more regular and only one simple thought about an object emerges in the spirit. Now it is sure to say that the state of dhyana is reached. Here, the spirit becomes very stable like the flame of a lamp in an atmosphere calms and its contact with the object of the experiment becomes intense and complete.
There are two varieties of sagunadhyana and nirgunadhyana called by dhyana. In the first dhyana, the calm one of the spirit is associated with an object of experiment which can be tested by the sensors. The second is completely mental. He implies the complete absorption of the spirit in itself. Here, the spirit is associated with no external object. It completely always becomes in this state. This spirit is supposed to remain always, quiet and sensitive such as it can about it include/understand beyond that, the event present and future which could be produced anywhere in the universe.