Progressive propaganda

 One Adolph Hitler

The receptivity of the great masses is very limited, their intelligence is small, but their power of forgetting is enormous. In consequence of these facts, all effective propaganda must be limited to a very few points and must harp on these in slogans until the last member of the public understands what you want him to understand by your slogan. 

http://www.mondopolitico.com/library/meinkampf/v1c6.htm