Harroll describes how the same idea can be conveyed in multiple different ways and forms, using symbols or text or a combination of the two. And even if they are representing the same idea, they can give the viewer a different connotation or feeling because of the choice of symbol/words. It’s also quite interesting how the symbol can have very different meaning when placed in a different context, which relates to Gestalt’s law of proximity, in which elements placed closer together are perceived as a coherent object, instead of as individual and separate objects.