Jung and Freud figured out that dreams can be turned into a science. A person who dreams of a brick house, for example means something specific, no matter what person is dreaming of a brick house. Symbols mean the same thing regardless of who is dreaming of the symbol. "But if the analyst who is confronted by this dream material uses Freud's original technique of 'free association,' he finds that dreams can eventually be reduced to certain basic patterns" (Carl Jung,
Man and His Symbols, p. 26).
"Freud made the simple but penetrating observation that if a dreamer is encouraged to go on talking about his dream images and the thoughts that these prompt in his mind, he will give himself away and reveal the unconscious back-ground of his ailments, in both what he says and what he deliberately omits saying. His ideas may seem irrational and irrelevant, but after a time it becomes relatively easy to see what it is that he is trying to avoid, what unpleasant thought or experience he is suppressing..." (ibid., p. 27).
"Sigmund Freud was the pioneer who first tried to explore empirically the unconscious background of consciousness...Before the beginning of this century, Freud and Josef Breuer had recognized that neurotic symptoms — hysteria, certain types of pain, and abnormal behavior—are in fact symbolically meaningful. They are one way in which the unconscious mind expresses itself, just as it may in dreams; and they are equally symbolic. A patient, for instance, who is confronted with an intolerable situation may develop a spasm whenever he tries to swallow: He 'can’t swallow it.' Under similar conditions of psychological stress, another patient has an attack of asthma: He 'can’t breathe the atmosphere at home.' A third suffers from a peculiar paralysis of the legs: He can’t walk, i.e., 'he can’t go on any more.' A fourth, who vomits when he eats, 'cannot digest' some unpleasant fact.
I could cite many examples of this kind, but such physical reactions are only one form in which the problems that trouble us unconsciously may express themselves. They more often find expression in our dreams" (ibid., p. 24-6).
And just to give you an idea of how scientific and reliable psychoanalysis and dream interpretation is:
"Freud worked in the laboratory of Ernst Brucke, one of a group of physiologists who had attempted to found a science of biology on thoroughly materialistic grounds. In his autobiography, Freud described Brucke as the person 'who carried more weight with me than anyone else in my whole life'" (Armand Nicholi Jr, The Question of God, p. 20).
"You may be surprised to learn that in Europe we have heard very frequently judgments passed on psychoanalysis by persons who knew nothing of its technique and had never practised it, but who demanded scornfully that we show the correctness of our results. There are among these people some who are not in other things unacquainted with scientific methods of thought, who for example would not reject the result of a microscopical research because it cannot be confirmed with the naked eye in anatomical preparations, and who would not pass judgment until they had used the microscope" (Sigmund Freud, The Origin & Development of Pscyhoanalysis, pp. 44-5).
Carl Jung correctly noted that many Christians today have forgotten that God still speaks today through dreams (Numbers 12:6).
“Christians often ask why God does not speak to them, as he is believed to have done in former days. When I hear such questions, it always makes me think of the rabbi who was asked how it could be that God often showed himself to people in the olden days while nowadays nobody ever sees him. The rabbi replied: 'Nowadays there is now longer anybody who can bow low enough.'
This answer hits the nail on the head. We are so captivated by and entangled in our subjective consciousness that we have forgotten the age-old fact that God speaks chiefly through dreams and visions. The Buddhist discards the world of unconscious fantasies as useless illusions; the Christian puts his Church and his Bible between himself and his unconscious; and the rational intellectual does not yet know that his consciousness is not his total psyche. This ignorance persists today in spite of the fact that for more than 70 years the unconscious has been a basic scientific concept that is indispensable to any serious psychological investigation” (Jung, Man and His Symbols).