Projection (defence mechanism)

Projection, along with denial and identification, are well-known psychological defence mechanisms which come out to play when an aspect of our identity is under psychological threat in some way.

As an example, consider that man is a social animal, and that it's common therefore for people to form social groups and to spend time with each other. Each individual will be a member of many different social groups---such as a particular church, a group of workers who regularly have lunch together, a group of friend which get together on weekends, a group of people with the same hobby (such as sailing), etc.

A person's identity and idea of self-value may be tied to which groups they belong and when that person is with particular groups of people they may tend to focus on or over-emphasise how other members of the group have similar interests or characteristics to the person themselves. In other words, they project aspects of themselves onto others in the manner of a movie projector, seeing things that aren't really there. This allows the person to get more of a feeling of belonging in the group than might otherwise be realistic.