A sketch of a familiar face can reveal how little you usually look closely.

Recognition is fast, and its speed is bought by skipping detail. After a few years you stop seeing a face and start seeing a label that stands for the person, which is why trying to draw one is so unsettling. The pencil asks where the eyes actually sit, and the label has no answer. Familiarity is not the same as attention, though it does a convincing impression of it.

Choose someone you see constantly and look at them properly for the length of a conversation. Ten minutes of bad drawing will teach it faster than any resolution to notice more.