Princess Margaret of Scotland astonished her courtiers by kissing the famously ugly poet Alain Chartier (c.1392-c.1430), 'for nature had, so far as Chartier was concerned, suffered a beautiful and rich mind to take up its abode in an ugly body.' The princess replied it was not the man she had kissed but the mouth from which so many golden words had proceeded. Therefore her kiss was an expression of respect and one we would now term Platonic.
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Christopher Nyrop, The Kiss and Its History, 1901