<unk> was first described by Sigmund Freud, and was later more clearly defined by his daughter Anna Freud.<unk> can be explained as thinking purely in extremes, e.g. good versus bad, powerful versus defenceless and so on. A two-year-old child cannot see a person, who does something unpleasant to the child (e.g. not feeding him when he is hungry), as possessing just one or a few bad characteristic(s). This is too complicated for the not yet fully developed brain. The other can only been seen as all bad at that moment in time. However, when this person gratifies the child, he will be perceived as all good again.<unk> can be seen as a developmental stage and as a defence mechanism.
Splitting 
Formication
Reading
Induction 
Sublimation 
Staining
Anise
Blocking 