The Power of Four is all around us, embedded in our mind, in our collective unconscious. Although the concept is no longer useful as the basis of scientific theory, it serves as an enduring metaphorical guidepost. It's been there from the dawn of history, whispering in our ear, guiding us, moving us forward in our understanding of ourselves and the world. Everywhere we turn there seem to be groups of four: four seasons, four directions, four elements, four humors, four cardinal virtues, four phases of the Moon, four states of matter, and let us not forget the Fantastic Four, Marvel Comics' four superheroes. Yes, four is all around us, and no more prevalent than in the evolution of the four elements of classical Greek philosophy to the four "families" of psychological types in contemporary personality theory.
