The Musical Man and the Bronze Statue: Aristotle's Examples in Physics I,7

In the first book of the Physics, Artistotle is concerned with the principles of natural philosophy, or more specifically, with the principles of change; for this is the common characteristic of natural phenomena, viz, that they are in a constant state of change or alteration. Having customarily begun with a discussion of the views of his predecessors - the Prescoratics Parmenides, Melissus, Anazimander, Empedocles, and Anazagoras, as well as Plato - in Chapter 5 Artistotle concludes that they all share the view that the principles must be contraries (188a19).