The Guide to Literary Terms defines "paradox" as "a statement that is apparently self-contradictory or absurd but really contains a possible truth."
Ordinarily, when someone smiles it is because that person feels pleasure or has heard something funny or is being amused. Judy Jones's smile, however, doesn't result from any emotion other than the need to attract people (especially men) to her. The paradox is that her smile has no emotion behind it; it amounts to nothing more than another layer of makeup added to enhance her beauty.
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