Who are the “professionals” and what is a “scientific discussion”? Am I right when I presume that you insinuate that every professional who has studied the matter is to be disregarded as unprofessional, since there really is no such thing?
As an example of historical significance: Carl Gustav Jung was a psychiatrist at Burghölzli mental institution and became famous in the psychiatric society at the time for his word association experiment. What he showed with this repeatable experiment was that there is an unconscious, that is, the conscious – the Ego – is not the master of one’s own psychology. The ego does not choose it’s own reactions on certain words.
What he would do was to read a list of a hundred words, to which the participant would say the first thing that came to his or her mind, and Jung took note of the participant’s reactions, and he found that certain words caused for instance hesitations, stuttering, phychical symptoms like blushing, perspirations, and so forth. He then read the same list once again and noted that those certain words once again caused these symptoms. The participant could not avoid them. For instance, a person who had a traumatic experience involving knife, blood and Vienna, could not choose not to show these symptoms when words associated with this experience were read to him or her. The psychological and physical reactions were involuntary, and they were of psychological origin. This was an example of evidence that there are what he called complexes, unconscious clusters of images, feelings, associations and so forth, that intervenes with the conscious mind. They are unconsciuos because we do not know about them and we do not rule them. The complexes pretty much rule us. We very much behave, and reacts, and feels, out of the motivation of our complexes rather than our concious will. One person do not mind if the boss says “That wasn’t a very good job”, the other person is devasted, because, for instance, the other person has a father complex which intervenes with his conscious mind. He know his reaction is irrational, but there it is; the involuntary blushing, the anxiety, the lot. This is of course, just a simplified example.
The point is that you can actually show that people are not masters of their own psychology. There is a conscious, parts of your psychology which you know and which you master. Right now, for instance, I’m conscious of what I’m doing and I decide every word I write and there are no emotions involved for instance. However, when my boss says: “Can’t you do anything right?” suddenly I react irrationally, I might not be able to speak at all, I blush, I’m enraged, and when I get home my wife says something and in the same instant I am not master of my own psychology and I say thing I never thought of saying and afterwards I might not even remember what I said; I am not conscious of what I am doing and if I watched a film of myself I might wonder who the hell is that; that is not “me”, because it is not my Ego conscious acting out but something else which is obviously part of my psychology. What is that? Moreover, that night I might have a dream about my father being dismissive in my childhood home. We must draw the conclusion that if this is not the conscious I, it must be my unconscios I; or, to talk with Jung (which I use as an example), a subconscious complex acting out.
But nobody can measure the length or the weight of the unconscious, and the next time a complex is triggered I might not have a dream about my father. So it is an unscientifical conclusion that my experience is a consequence of my unconscious. Nonetheless, there it is: My own psychology is intervening with my psychology, I am not to chose my own reactions, my own associations, my own dreams. We can only say that our own psychology is not in our own hands, it seems to be, at least at times, in some “other’s” hands. What is that “other” of ours?
But the study of the unconscious, which is a reality, everybody who has the slightest talent for introspection knows that, does however not lend itself easily to the rules of natural science. The word association experiment (with all its faults, Jung himself abandoned it later) is an example on how close we can get – interesting because of its historical importance (Freud became very interested in Jung’s studies because of it for instance, because he very much wanted his theories to fit in a scientific discourse) --, but it is not enough for “science”. We cannot repeat it, we do not know that the reason I dream about my dismissive father after my boss rejects my work because of a father complex, because the next time I have this experience I might not dream about my father, and we cannot see the complex. All we can do is note the symptoms. But this is the case also in physics. We are convinced that gravitation is a fact because of the symptoms, and we can work out a working hypothesis for why there is such a thing as gravitation, but we cannot see it. We cannot say: Here is your gravitation to see. And we cannot say: Here is your unconscious. We can only say: Everything points to the fact that there is an unconscious, and here’s our hypothesis on what it is and how it works, from what we gather from the overwhelming material we have from its symptoms. But no, there is no scientific proof that it exists because although we can measure its effects, we cannot measure it in itself. Therefore we can easily say: There is no unconscious, and you can never prove to me, “scientifically”, that there is. But, “yet it moves.”