Cathedral with a fly inside Symbol Analysis

When Bryson describes the structure of an atom, he uses the metaphor of a “cathedral with a fly inside” to illustrate the notion that the vast majority of an atom is empty space. The fly represents the atom’s nucleus, and the cathedral walls represent the outer edges of the atom. Curiously, the nucleus is much, much heavier than the rest of the atom. To help the reader conceptualize this, Bryson says imagine the fly is heavier than an actual cathedral and that the rest of the atom weighs as much as a fly. Bryson appeals to metaphors like this to help the reader visualize and engage with scientific information that’s difficult to conceptualize from abstract technical writing. In invoking the metaphor, Bryson also prompts the reader to experience amazement about the curious nature of atoms—the tiny particles that make up everything in existence.