Here’s a Latin poem from mid-1st century BCE Rome (poem 39 by Catullus) with one answer:
Egnatius, because he has bright white teeth,
always smiles: If someone comes to the defendant’s
bench, when the speaker arouses weeping,
he grins; If there is mourning at the funeral pyre of
a dutiful son, when the bereaved mother weeps for her only son,
he grins. Whatever it is, wherever he is,
whatever he is doing, he grins: he has this disease,
neither elegant, I think, nor refined.
Therefore I must warn you, my good Egnatius.
If you were a city man or a Sabine or a Tiburnan
or a thrifty Umbrian or a fat Etruscan
or a swarthy and toothy Lanuvian or
a Transpadane, to touch on my own people as well,
or anyone you like who cleans his teeth with clean water,
I still should not want you to smile on all occasions:
for nothing is more silly than a silly smile.
Now you are a Celtiberian: in the land of Celtiberia,
whatever each man has urinated, with this he is accustomed
in the morning to rub his teeth and his red gums,
so that the more polished those teeth of yours are,
the more urine they proclaim you to have drunk.
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