The universe is only an object created by the mind and has its being in the mind.

Ramana Maharishi:  The mind is something mysterious. It consists of satva, rajas and tamas. The latter two give rise to vikshepa. In the satva aspect, it remains pure and uncontaminated. So there are no thoughts there and it is identical with the Self. The mind is like akasa (ether). Just as there are the objects in the akasa, so there are thoughts in the mind. The akasa is the counterpart of the mind and objects are of thought. One cannot hope to measure the universe and study the phenomena. It is impossible. For the objects are mental creations. To measure them is similar to trying to stamp with one’s foot on the head of the shadow cast by oneself. The farther one moves the farther the shadow does also. So one cannot plant one’s foot on the head of the shadow. (Here Sri Bhagavan related several incidents connected with shadows including the pranks of monkeys and a mirror). A child sees his own shadow and tries to hold the head of the shadow. As he bends and puts out his arm the head moves further. The child struggles more and more. The mother, seeing the struggle, pities the young one. So she takes hold of the young hand and keeps it on his own head and tells the child to observe the head of the shadow caught in the hand. Similarly with the ignorant practiser to study the universe. The universe is only an object created by the mind and has its being in the mind. It cannot be measured as an exterior entity. One must reach the Self in order to reach the universe. Again people often ask how the mind is controlled. I say to them, “Show me the mind and then you will know what to do.” The fact is that the mind is only a bundle of thoughts. How can you extinguish it by the thought of doing so or by a desire? Your thoughts and desires are part and parcel of the mind. The mind is simply fattened by new thoughts rising up. Therefore it is foolish to attempt to kill the mind by means of the mind. The only way of doing it is to find its source and hold on to it. The mind will then fade away of its own accord. Yoga teaches chitta vritti nirodha (control of the activities of the mind). But I say Atma vichara (Self-investigation). This is the practical way. Chitta vritti nirodha is brought about in sleep, swoon or by starvation. As soon as the cause is withdrawn there is recrudescence of thoughts. Of what use is it then? In the state of stupor there is peace and no misery. But misery recurs when the stupor is removed. So nirodha (control) is useless and cannot be of lasting benefit. How then can the benefit be made lasting? It is by finding the cause of misery. Misery is due to objects. If they are not there, there will be no contingent thoughts and so misery is wiped off. “How will objects cease to be?” is the next question. The shrutis and the sages say that the objects are only mental creations. They have no substantive being. Investigate the matter and ascertain the truth of the statement. The result will be the conclusion that the objective world is in the subjective consciousness. The Self is thus the only Reality which permeates and also envelops the world. Since there is no duality, no thoughts will arise to disturb your peace. This is Realisation of the Self. The Self is eternal and so also its Realisation. In the course of the discourse Sri Bhagavan also made a few points clearer: Abhyasa consists in withdrawal within the Self every time you are disturbed by thought. It is not concentration or destruction of the mind but withdrawal into the Self. Dhyana, bhakti, japa, etc., are aids to keep out the multiplicity of thoughts. A single thought prevails which too eventually dissolves in the Self.