This is the person often mentioned in Bob Frissell’s book:
Inside
“The state of mind of the photographer creating is a blank. I might add that this condition exists only at special times, namely when looking for pictures. (Something keeps him from falling off curbs, down open manholes, into bumpers of skidding trucks while in this condition but goes off duty at other times.) ... This is a very special kind of blank. A very active state of mind really, it is a very receptive state ...”