Whoever denies the existence of the unconscious is in fact assuming that our present knowledge of the psyche is total. And this belief is clearly just as false as the assumption that we know all there is to be known about the natural universe.
Our psyche is part of nature, and its enigma is as limitless. Thus we cannot define either the psyche or nature. We can merely state what we believe them to be and describe, as best we can, how they function.
Quite apart, therefore, from the evidence that medical research has accumulated, there are strong grounds of logic for rejecting statements like “There is no unconscious.”
Those who say such things merely express an age-old “misoneism” — a fear of the new and the unknown.