people...

We don't see things as they are, we see them as we are.

(Anais Nin)

There is seldom such a thing as an absolute truth. Everything we see and hear causes us to come to a conclusion about what we have seen or heard based upon our own experiences up to that point.

A magician will deliberately use our way of perceiving things to suggest that something impossible has just taken place, and therefore entertain us.

A man boarded a tube train with three children and sat in the corner seat while the children started playing loudly and running up and down the carriage. After several stops the other passengers were becoming increasingly annoyed and one of them eventually spoke to the man, asking why he didn’t keep his children under control. The man raised his head slowly and looking over to where his children were playing apologised to the other passenger saying he had not really been thinking about the children, he had just come from the hospital were his wife had, after a short illness, died, that morning. The passenger had failed to see things as they were because his own perception had only included the children, not the grieving father.
At work the same thing is true. People will make assumptions about others or about situations based on a perception that has been created in the past and has no relevance to the current situation.