When mother smiled, no matter how nice her face had been before, it became incomparably nicer and everything around seemed to brighten up as well. If, at difficult moments of my life, I were able even fleetingly to see this smile, I would not know the meaning of sorrow. It seems to me that what people call the beauty of a face is constituted by its smile: if a smile adds glory to a face, then that face is beautiful; if it does not change it, it is ordinary; and if it spoils it, it is ugly.
Leo Tolstoy, Childhood.

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