Aristotle the Great (300 BCE)
Philosopher-king extraordinaire, Aristotle was known for his love of categorizing things. He was the original "if it doesn't fit, we'll make it fit" type.
Confucius the Wise (500 BCE)
Chinese sage and all-around nice guy, Confucius taught that moderation was key. Too bad his students didn't listen.
Thomas Jefferson (1800 CE)
Founding father and master of compromise, Jefferson brought us the art of doing just enough to get by. Moderatorial greatness, indeed.