Introduction

The idea that the personality or states of mind could cause disease has a long history. The Roman physician Galen suggested that imbalances in the four bodily humours create both mental states and physical diseases. The four bodily humours were those proposed by the ancient Greek Hippocrates, many years before, namely blood, black and yellow bile and phlegm. Galen used Hippocrates' proposal to suggest, for example, that melancholic women (i.e., depressed women) were more likely to develop cancer, as both depression and cancer were caused by an excess of black bile. In addition to medical texts based on the Hippocratic medical tradition, there are many examples in the literature of mind states influencing disease, in particular those relating to the idea of a ‘broken heart’ (Lynch 1977). For example, John Donne's (1572–1631) poem ‘The broken heart’ suggests that lost love could lead to disease, including the plague. There is a Japanese myth of an octopus farmer who, spurned by the octopus with whom he had fallen in love, died of a broken heart. The ‘broken heart leading to disease and death’ concept is worldwide.

The relationship between personality and disease is important because it provides insights into the idea of dysregulation. Infornet dysregulation has a number of psychological consequences, including consequences for personality. Thus, the personality–disease relationship is part of the way dysregulation manifests psychologically. This chapter on the meaning of infornet dysregulation therefore starts with an examination of research on the personality–disease relationship.