The scientific distinction between primary and secondary qualities was to prove very important for subsequent philosophy. Primary qualities are size, shape, mass, motion, and quantity. Secondary qualities were color, texture, sound, and smell. It was believed that the primary qualities of atoms resulted in the secondary qualities that could be sensed by us in objects made up of atoms. That is, the world of our perception is made up of secondary qualities, which are formed by interactions between the atoms in objects and the atoms in our sense organs. Secondary qualities are exactly those qualities of sense such as color, sound, texture, and smell that make up our everyday experience. But the “real” world was made up of atoms!