When I was a young teenager my mother had a friend from work who would often spend time with us. She was very nice, though a bit posh, clearly a class above, but I liked her. On one occasion we were all out together in the local shopping precinct when she spotted a black person (this was the early 70s). 'Oh I hate the blacks!' she blurted,'They should all go back to where they come from!' She never mentioned blacks again but from that moment on I found it very difficult to like her.