Here is an excerpt from the Indian spiritual genius and savant Swami Vivekananda’s (1863-1902) book ‘ Raja Yoga’.
" We find , in studying history, one fact held in common by all the great teachers of religion the world ever had . They all claim to have got their truths from beyond, only many of them did not know where they got them from. For instance, one would say that an angel came down in the form of a human being, with wings, and said to him, “Hear, O man, this is the message”.Another says that a Deva, a bright being, appeared to him. A third says he dreamed that his ancestor came and told him certain things. He did not know anything beyond that .But this is common that all claim that this knowledge has come to them from beyond, not through their reasoning power. What does the science of Yoga teach? It teaches that they were right in claiming that all this knowledge came to them from beyond reasoning, but that it came from within themselves.
The Yogi teaches that the mind itself has a higher state of existence, beyond reason, a superconscious state, and when the mind gets to that higher state,then this knowledge, beyond reasoning, comes to man . Metaphysical and transcendental knowledge comes to that man .This state of going beyond reason, transcending ordinary human nature, may sometimes come by chance to a man who does not understand its science; he , as it were, stumbles upon it. When he stumbles upon it, he generally interprets it as coming from outside. So this explains why an inspiration, or transcendental knowledge, may be the same in different countries, but in one country it will seem to come through an angel, and in another through a Deva, and in a third through God. What does it mean? It means that the mind brought the knowledge by its own nature, and that the finding of the knowledge was interpreted according to the belief and education of the person through whom it came. The real fact is that these various men, as it were, stumbled upon this superconscious state.
The Yogi says there is a great danger in stumbling upon this state. In a good many cases there is the danger of the brain being deranged, and , as a rule, you will find that all those men, however great they were, who had stumbled upon this superconscious state, without understanding it, groped in the dark, and generally had, along with their knowledge, some quaint superstition. They opened themselves to hallucinations. Mohammed claimed that the Angel Gabriel came to him in a cave one day and took him on the heavenly horse, Harak, and he visited the heavens. But with all that , Mohammed spoke some wonderful truths. If you read the Koran, you find the most wonderful truths mixed with superstitions. How will you explain it? That man was inspired, no doubt, but that inspiration was, as it were, stumbled upon. He was not a trained Yogi, and did not know the reason of what he was doing. Think of the good Mohammed did to the world, and think of the great evil that has been done through his fanaticism! Think of the millions massacred through his teachings, mothers bereft of their children, children made orphans, whole countries destroyed, millions upon millions of people killed!
So we see this danger by studying the lives of great teachers like Mohammed and others. Yet we find, at the same time , that they were all inspired. Whenever a prophet got into the superconscious state by heightening his emotional nature, he brought away from it not only some truths, but some fanaticism also, some superstition which injured the world as much as the greatness
RE: The real cause of Islamic terrorism
Here is an another excerpt from Swami Vivekananda's 'Raja Yoga' dealing with the subject of superconsciousness or enlightenment.
"When I eat food, I do it consciously; when I assimilate it, I do it unconsciously. When the food is manufactured into blood, it is done unconsciously.When out of the blood all the different parts of my body are strengthened , it is done unconsciously. And yet it is I who am doing all this; there cannot be twenty people in this one body. How do I know that I do it, and nobody else?It may be urged that my business is only in eating and assimilating the food, and that strengthening the body by the food is done for me by somebody else. That cannot be, because it can be demonstrated that almost every action of which we are now unconscious can be brought up to the plane of consciousness. The heart is beating apparently without our control. None of us here can control the heart; it goes on its own way. But by practice men can bring even the heart under control, until it will beat at will, slowly, or quickly, or almost stop. Nearly every part of the body can be brought under control. What does this show? That the functions which are beneath consciousness are also performed by us, only we are doing it unconsciously.
We have, then,two planes in which the human mind works. First is the conscious plane , in which all work is always accompanied with the feeling of egoism. Next comes the unconscious plane, where all work is unaccompanied by the feeling of egoism. That part of mind-work which is unaccompanied with the feeling of egoism is unconscious work, and that part which is accompanied with the feeling of egoism is conscious work. In the lower animals this unconscious work is called instinct. In higher animals, and in the highest of all animals, man, what is called conscious work prevails.
But it does not end here. There is a still higher plane upon which the mind can work. It can go beyond consciousness. Just as, unconscious work is beneath consciousnes, so there is another work which is above consciousness and which also is not accompanied with the feeling of egoism. The feeling of egoism is only on the middle plane. When the mind is above or below that plane, there is no feeling of "I", and yet the mind works. When the mind goes beyond this line of self-consciousness, it is called Samadhi, or superconsciousness. How , for instance, do we know that a man in Samadhi has not gone below consciousness, has not degenerated instead of going higher?In both cases the works are unaccompanied with egoism. The answer is, by the effects, by the results of the work, we know that which is below, and that which is above. When a man goes into deep sleep, he enters a plane beneath consciousness. He works the body all the time, he breathes , he moves the body, perhaps , in his sleep, without any unaccompanying feeling of ego; he is unconscious, and when he returns from his sleep, he is the same man who went into it. The sum total of the knowledge which he had before he went into the sleep remains the same; it does not increase at all. No enlightenment comes. But when a man goes into Samadhi, if he goes into it a fool, he comes out a sage.
What makes the difference? From one state a man comes out the very same man that he went in , and from another state the man comes out enlightened, a sage, a prophet, a saint, his whole character changed, his life changed, illumined. These are the two effects. Now the effects being different, the causes must be different. As this illumination with which a man comes back from Samadhi is much higher than can be got by reasoning in a conscious state, it must , therefore, be superconsciousness, and Samadhi is called the superconscious state."
RE: The real cause of Islamic terrorism
These prophets were not unique; they were men as you or I. They were great Yogis. They had gained this superconsciousness, and you and I can get the same. They were not peculiar people. The very fact that one man ever reached that state proves that it is possible for every man to do so. Not only is it possible, but every man must, eventually, get to that state, and that is religion.
--Swami Vivekananda