The criteria for the diagnosis of anorexia nervosa include refusal to maintain minimal normal weight with bodyweight less than 85% of that expected for age and height, fear of becoming fat or gaining weight, disturbance in body weight and shape perceptions, absence of at least three normal non-drug induced consecutive menstrual cycles.The current International Classification of Diseases (ICD-10) states that though the condition occurs most commonly in adolescent girls and young women, adolescent boys and young men may also be affected rarely, as well as children approaching puberty and older women up to menopause.In extreme cases, bizarre eating patterns can lead to life-threatening medical conditions, which require hospitalisation. Anorexia is thought to be due to a complex interplay between psychological, biological, and socio-cultural causes.Before the existence of the theory of dualism, it was considered that the mind and body were the same. This view was called monism, which proposes that behaviour is strictly a function of physical events.Typically, the physical events are associated with or are directly a function of brain activity. Boring (1950) suggested, The chief function of the brain is thought, perhaps, or consciousness. Hence, the behaviour could be considered a direct outcome primarily of brain activity.The doctrine of mind/body dualism was recognised since the time of Plato, but it was Rene Descartes (1596-1650) who reworked this concept of dualism into a form, which fitted to the times (Lowry et al., 1982). Philosophers subsequently referred this as Cartesian dualism. According to this theory, the mind and the body are two distinct entities.Descartes argues for his theory by saying that as he is a subject of conscious thought and experience, he thus, cannot be anything more than spatially extended matter. The mind cannot be material but must be non-material.