If a person feels terrible, it usually should not be shown or acknowledged during a greeting exchange. Instead, the unhappy person is expected to conceal negative feelings, putting on a polite smile to accompany the “Just fine, thank you, and how are you?” reply to the “How are you today?” The true feelings will probably go undetected, not because the smile is such a good mask but because in polite exchanges people rarely care how the other person actually feels.