"You say there are two types of people?"
... "You say there are two types of people?"
"Yes, those who separate people into two groups and those that don't."
"Wrong. There are three groups:
Those who separate people into three groups...
(1) A sheet of paper is an ink-lined plane.
(2)... (1) A sheet of paper is an ink-lined plane.
(2) An inclined plane is a slope up.
(3) A slow pup is a lazy dog.
QED: A sheet of paper is a lazy dog.
-- Willard Espy, "An Almanac of Words at Play"