When my head was not to be trusted

"A writer, if he is any good, does not describe. He invents or makes out of knowledge personal and impersonal and sometimes he seems to have unexplained knowledge which could come from racial or family experience. Who teaches the homing pigeon to fly as he does; where does a fighting bull get his bravery, or a hunting dog his nose? This is an elaboration or a condensation on that stuff we were talking about in Madrid that time when my head was not to be trusted." --Ernest Hemingway, The Paris Review Interviews, I