Rivers starts by pointing out that the term 'Complex', though at first used by Jung without any precise definition, soon came to denote 'a system which has become or tends to become separated from the rest of the mental structure or personality and by its domination of the mind has destroyed or tends to destroy the unity which is essential to mental health'. The meaning of the term was extended by Hart to denote any emotionally toned system of ideas which determines conscious behaviour, the hobby and political bias being taken as examples. In this broad sense it becomes almost if not quite identical with the sentiment of recent British psychology. A sentiment may be defined as an organized system of emotional tendencies grouped about an object. Rivers suggests