Being that we are tribal in nature and have lived in tribal cultures for far longer than we have lived in individualistic ones, there is a strong propensity to be swayed by appeals to tribalistic urges, including negative propaganda, negative rumours and negative stereotypes. Sometimes we need no external catalyst, but are primed to categorise someone and assume the worst of someone on the basis of a perceived shared identity, ignoring and collapsing the likely complex self-identity of individuals on the basis of limited information and experience. This tendency is countered most effectively by personal knowledge of people from many different backgrounds