Sorting Things Out
Upon arriving at Hogwarts school for wizards, and before sitting down to the welcoming banquet, Harry Potter and all the other first year students (in J.K. Rowling's marvelous series of Harry Potter novels) are asked to take part in the serious and scary business of the Sorting Ceremony.
An ancient wizard's hat, patched and frayed, is placed upon a four-legged stool in the middle of the school's Great Hall. This is the Sorting Hat, and each new student is called, one by one, to approach the stool and put on the hat. The Sorting Hat is magically alive, you see, and its job is to listen to each student's thoughts for a few moments, trying to catch the note of his or her true nature, and then to call out, through a tear near the brim, which of the four residence houses the student will call home. Each house at Hogwarts has its own noble history and its own unique character -- almost exactly fitting the four temperaments, by the way -- and the Sorting Hat makes sure that the personality of the student and the character of the house are well suited to each other.
Slytherin is the house for students known as being 'resourceful...with a certain disregard for rules,' also 'shrewd' and 'cunning folk [who] use any means to achieve their ends.' Sounds suspiciously like Keirsey's Artisans.
Hufflepuff is home to students who are 'hard workers,' also 'just and loyal,...patient...true, and unafraid of toil.' Who but Keirsey's Guardians?
Gryffindor welcomes those students known for their 'chivalry,' and who are willing to fight for what is 'right and good.' Very much like Keirsey's Idealists.
Ravenclaw is the 'wise old' house, reserved for only the 'cleverest' students, those of 'ready mind...wit and learning. Definitely Keirsey's Rationals.