Who is PT Barnum from The Image: A Guide to Pseudo-events in America and what is their importance?

The author describes PT Barnum as a "notorious pioneer" in advertising. Barnum himself boasted about his talent in turning every event towards his own personal gain through the use of advertising techniques. One of these was a kind of "compounding pseudo-events" in which he constructed a pseudo-event and then created a second pseudo-event that was based on the first one. He kept this creation going as long as he could in order to increase his publicity as much as possible.