Imagine walking into a large room filled with people clothed in colors indicating the number of things they have in common with you: white indicating nothing in common, light green meaning one thing, orange for two things, etc., on up to, say, purple indicating that you have twenty or more things in common with that individual. Now imagine everyone grouped by color, those in white off to your right, those wearing light green to their right, etc. By simply looking at anyone in one of these grou