Antar mouna stage 1 is concerned with stimuli and experiences which come from outside; antar mouna stage 2 is concerned with those experiences, thoughts, memories, visions and emotions which arise from inside the mind.
The purpose of this stage is to exhaust negative thoughts, complexes, phobias, etc. from the subconscious mind. In Sanskrit these thoughts are called samskaras.
Throughout life we tend to allow good thoughts to arise to conscious perception, but try to suppress bad thoughts. If a pleasant thought arises we accept and enjoy it and perhaps even dwell on it. On the other hand, if an unpleasant, nasty thought arises we tend to quickly push it back into the subconscious layers of the mind. This is called suppression and each suppressed thought remains unexpressed and emotionally charged; it acts as a block in the mind.
In life we build up a vast accumulation of suppressed thoughts. They cause unhappiness and tension in life. They keep the mind in a continual state of disturbance. They tend to cause states of depression and dissatisfaction without any obvious reason, yet the reason is almost certainly to be found in the form of suppressed thoughts. The purpose of antar mouna stage 2 is to slowly exhaust these thoughts, to purge the mind. It is a process of mental shankhaprakshalana.
Antar mouna stage 2 is concerned with passive awareness of the thinking process. One should allow all thoughts to arise in the mind without suppression. Some thoughts may be disagreeable and repulsive, but don’t reject them. Even if you have thoughts of murder, revenge, jealousy, hatred, etc. you should not suppress them. Allow all thoughts to bubble up without exception.
Do not make any effort to create thoughts. Let them arise naturally . . . and disappear naturally. It is not necessary to try to think, only let the thoughts arise spontaneously. Simultaneously you should try to be a witness of the thinking. You should try to remain a disinterested spectator of everything that occurs in your mind.
You may experience periods of time where the mind seems blank, thoughts stop. It is unlikely that you are in samadhi. This period of blankness means that you have habitually fastened down the lid of the mind so tightly that thoughts cannot arise freely. That is, strong suppression prevents thoughts arising. Merely watch the mind and thoughts will soon start to arise again. Do not try to create thoughts during these periods of blankness. Only wait for the spontaneous flow of thoughts to start again.
After regular practice over a period of time you may start to see thoughts that you did not think existed in your mind. You may relive childhood memories. Thoughts will arise which you tried hard to forget. Fears may show themselves very vividly: fear of snakes, spiders, mice, fear of drowning, fear of the dark and so many other mental phobias. Whatever arises, try to remain an impassive witness.
As you begin to perceive deeper parts of the subconscious mind you may see visions – they may be beautiful or they may be grotesque and frightening. These are the more subtle forms of thoughts. Let them arise without suppression. Merely observe them without like or dislike. These visions must also be exhausted for they too are part of the veil of the subconscious mind.
Regular practice of antar mouna stage 2 will gradually purge the mind of suppressed thoughts. Eventually it can lead to a state of mental tranquillity and one-pointedness.