" One idea led to another, and in his relaxed mood he found that this “free association” had stirred up many old memories. Among them he was annoyed to find some long-buried disagreeable topics—things he had wished to forget and had forgotten consciously. He had in fact arrived at what psychologists would call his “complexes”—that is, repressed emotional themes that can cause constant psychological disturbances or even, in many cases, the symptoms of a neurosis. "

― C.G. Jung , Man and His Symbols