one thing is certain: it is the complexes (emotionally-toned contents having a certain amount of autonomy) which play the most important part here. The term "autonomous complex" has often met with opposition, unjustifiably, it seems to me, because the active contents of the unconscious do behave in a way I cannot describe better than by the word "autonomous." The term is meant to indicate the capacity of the complexes to resist conscious intentions, and to come and go as they please. Judging by all we know about them, they are psychic entities which are outside the control of the conscious mind. They have been split off from consciousness and lead a separate existence in the dark realm of the unconscious, being at all times ready to hinder or reinforce the conscious functioning. [924] A deeper study of the complexes leads logically to the problem of their origin, and as to this a number of different theories are current. Theories apart, experience shows that complexes always contain something like a conflict, or at least are either the cause or the effect of a 719 conflict. At any rate the characteristics of conflict-shock, upheaval, mental agony, inner strife-are peculiar to the complexes. They are the "sore spots," the bêtes noires, the "skeletons in the cupboard" which we do not like to remember and still less to be reminded of by others, but which frequently come back to mind unbidden and in the most unwelcome fashion.
— Carl Gustav Jung
Jung's insistence on the word "autonomous" is worth pausing over. He is not speaking loosely or dramatically — he means it technically, as a description of observed behavior: these contents resist, they arrive uninvited, they depart without permission, and no act of will reliably governs them. The conscious mind does not own its own house, and the complexes are proof.
What the passage names as "sore spots" and "skeletons in the cupboard" is precisely the material that most of us have already tried to handle through some version of sufficient effort — understanding it enough, leaving it behind, resolving it once, transcending it through the labor of self-improvement. The complex does not cooperate. It comes back unbidden, in the most unwelcome fashion, because it was never held by the strategies we brought to it. It was split off before those strategies existed, and it carries the charge of that original conflict regardless of what has been layered on top.
This is what Jung means when he says a complex "always contains something like a conflict." Not merely a memory, not merely a pattern — a knot of tension that was never discharged. The skeletons do not stay in the cupboard. That is not a failure of willpower or self-knowledge. It is the structure of the psyche announcing itself.
Carl Gustav Jung·Psychological Types·1921