He wanted to formulate a systematic way of analyzing the mind to treat patients with hysteria and in ways never thought of before. Thus was born his theory of psychoanalysis which was his solution to mental illness. He invited his patients to lie down on a sofa and talk freely or in free association about what was on their minds, whether appropriate or not. This, as previously mentioned, was his creation and served as a laboratory for his theories, as in the case study of Anna O. where he originally theorized that mental illness is nothing more than a physical manifestation of repressed memories and emotions. This had never been heard of before in psychology, where most illnesses were treated as strictly biological rather than induced by a deeper cause. Although Freud argued that this theory is merely subjective, “the patient's “free” associations provide only spurious confirmation of psychoanalytic interpretations, because they are after all so strongly contaminated by the influence of the therapist” (Qtd. in Rothstein). Freud's analysis of a given patient depended on how we felt that day or whether he had used drugs or not. The analysis could easily have been frustrated by any internal emotions he might have felt and then coped with it