in his career through the word association tests conducted at the Burghölzli, the psychiatric clinic of Zurich University, where he worked from 1900 to 1908. In the word association tests, a researcher would read a list of 100 words to a subject, who was asked to say, as quickly as possible, the first thing that came to mind in response to each word, and the subject's reaction time was measured in fifths of a second. (Sir Francis Galton invented the method in 1879.) Researchers noted any unusual reactions—hesitations, slips of the tongue, signs of emotion. Jung was interested in patterns he detected in subjects' responses, hinting at unconscious feelings and beliefs. In Jung's theory, complexes may be conscious, partly conscious, or unconscious. As well, complexes can be positive or negative, resulting in good or bad consequences. There are many kinds of them, but at the core of any complex is a universal pattern of experience, or archetype. Two of the major complexes Jung wrote about were the anima (a node of unconscious beliefs and feelings in a man's psyche relating to the opposite gender) and animus (the corresponding complex in a woman's psyche). Other major complexes include the mother, father, hero, and more recently, the brother and sister. Jung believed it was perfectly normal to have complexes because everyone has emotional experiences that affect the psyche. Although they are normal, negative complexes can cause us pain and suffering. One of the key differences between Jungian and Freudian theory is that Jung's thought posits several different kinds of complex. Freud only focused on the Oedipus complex which reflected developmental challenges that face every young boy. He did not take other complexes into account except for the Electra complex, which he briefly spoke of. After years of working together, Jung broke from Freud, due to disagreements in their ideas, and they each developed their own theories. Jung wanted to distinguish between his and Freud's findings, so he named his theory "analytical psychology". Jung's theory of complexes with key citations The ego itself can be thought of as a complex, not yet fully integrated with other parts of the psyche (namely, the superego and the id, or unconscious). As described by Jung, "by ego I understand a complex of ideas which constitutes the center of my field of consciousness and appears to possess a high degree of continuity and identity. Hence I also