When someone goes to the doctor and says, "I hear a voice in my head," he or she will most likely be sent to a psychiatrist. The fact is that, in a very similar way, virtually everyone hears a voice, or several voices, in their head all the time: the involuntary thought processes that you don't realize you have the power to stop. Continuous monologues or dialogues. You have probably come across "mad" people in the street incessantly talking or muttering to themselves. Well, that's not much different from what you and all other "normal" people do, except that you don't do it out loud. The voice comments, speculates, judges, compares, complains, likes, dislikes, and so on. The voice isn't necessarily relevant to the situation you find yourself in at the time; it may be reviving the recent or distant past or rehearsing or imagining possible future situations. Here it often imagines things going wrong and negative outcomes; this is called worry. Sometimes this soundtrack is accompanied by visual images or "mental movies." Even if the voice is relevant to the situation at hand, it will interpret it in terms of the past. This is because the voice belongs to your conditioned mind, which is the result of all your past history as well as of the collective cultural mind-set you inherited. So you see and judge the present through the eyes of the past and get a totally distorted view of it. It is not uncommon for the voice to be a person's own worst enemy. Many people live with a tormentor in their head that continuously attacks and punishes them and drains them of vital energy. It is the cause of untold misery and unhappiness, as well as of disease. The good news is that you can free yourself from your mind. This is the only true liberation. You can take the first step right now. Start listening to the voice in your head as often as you can. Pay particular attention to any repetitive thought patterns, those old gramophone records that have been playing in your head perhaps for many years. This is what I mean by "watching the thinker," which is another way of saying: listen to the voice in your head, be there as the witnessing presence. When you listen to that voice, listen to it impartially. That is to say, do not judge. Do not judge or condemn what you hear, for doing so would mean that the same voice has come in again through the back door. You'll soon realize: there is the voice, and here I am listening to it, watching it. This I am realization, this sense of your own presence, is not a thought. It arises from beyond the mind.
— Eckhart Tolle