Ah… What luck.. I have here in front of me a book “A Dictionary of Omens and Superstitions”.
Under the entry “Sneezing”:
Many people still regard the saying of ‘Bless You’ to someone who sneezes as superstitious, but in fact when ‘God bless you’ was said in Roman times, the sound of someone sneezing was very often the first indication that he had caught the plague, so the blessing might as well have been an expression of sympathy and despair, as those nearby hurried from the presence of the victim.
Of course, as always, it’s worth taking things with a pinch of salt, as not too far down the book also says that:
In America, if you sneeze while speaking, it is a sign to everyone that are telling the truth; while if you sneeze at table you will have a new friend before the next meal. The Americans also believe that if you sneeze as you set out on a mission, you will fail in it; but if you want to sneeze but cannot, it is a sign that someone loves you but dare not tell you.
Errmmmm… If that’s true, then that’s a pretty unsettling explanation for my inability to sneeze when trying to test out Grisaille’s Nipple-Hardening Sneeze Theory..