Earth - Fire - Water - Air: According to the four element theory of temperaments, earth, fire, air and water are the building blocks of the universe. Without them, life would not exist. They shape our view of the world around us, affect our thoughts and guide our feelings. Classifying our cosmos according to the four elements is probably one of the oldest principles of mankind, dating back to the ancient Greeks, and maybe even before them. While we know more about the elements and atoms, these f...