The doctrine of concordia discors - the idea that the numerous conflicts between the four elements in nature (air, earth, fire and water) paradoxically create an overall harmony in the world - can be traced back to the Greek philosophers, Pythagoras (c. 580-500 B.C.), Heraclitus (c. 544-483 B.C.) and Empedocles (c. 490-430 B.C.). The Latin phrase which is used to encapsulate the idea was first used by Horace in the twelfth epistle of his first book (c. 20 B.C.) to describe Empedocles’ philosophy that the world is explained and shaped by a perpetual strife between the four elements, ordered by love into a jarring unity, or, as the musical metaphor held it, a “discordant harmony”.