To monitor our surroundings is to focus on what's outside of ourselves: what we see, hear, smell, feel, and perhaps even taste. But sometimes what really marks a place is something less specific ─ a feeling within us. An interesting example emerged from a study of subway passenger behavior. Researchers trying to understand why people sit where they sit or stand where they stand in subway and metro trains examined the factors that shape the way riders used and navigated that space in different situations. One of their findings involved the reasons many riders like to plant themselves close to the train's doors. Partly this was the obvious convenience of being able to exit more quickly. But it was shaped partly by a more abstract sensation ─ the desire to avoid the sometimes uncomfortable feeling of accidentally making eye contact with seated passengers. We can't see feelings ─ but they're very real, and they influence our experience of the world.