In Chapter 1, “The Things that Fill the World,” Leslie Armour tries to determine of what “the world,” construed as the amalgam of objects we think we encounter directly and the theoretical entities of physics, consists. He argues that even the objects we think we encounter directly---chickens, works of art, coins, account books, automobiles, etc.—require a good deal of “making” on our part if we are even to perceive them. It takes a lot of concepts and mental activity to see an automobile. As Gilbert Ryle was fond of saying, “seeing” is an achievement verb. In this sense, the things that physicists talk about—electrons, protons, neutrons, quarks, etc.—are not unlike the objects we think we encounter directly since the mental apparatus required to understand both types of objects is considerable.