Q: Why do celebrities kiss both cheeks of everyone they come into contact with? It just seems so fake. When did this greeting begin?

Carrie Brunori,

Alexandria

A: Cheek kissing goes way back through most Western civilizations, and it has always made everyone involved feel a little more Hollywood, even when there wasn't a Hollywood. According to some theologians' parsing of the New Testament, Paul and other celebs of the early Christian movement greeted one another with three alternating kisses on the cheek. (Mwah, mwah and mwah: Father, Son, Holy Ghost.)

Once thought to be the fey act of Europeans and divas (or men in drag), the cheek kiss has become a matter of course in everything except politics and sports, and is increasingly popular with thekids. Since it isn't going away, here are some rules: Male celebrities over 35 never kiss another guy on the cheek, unlike some of their younger counterparts. Every kiss must make contact (no '80s-style "Dynasty" air kisses allowed). No men kiss David Letterman and Jay Leno, but all women are required to. And nobody kisses the press. (In the last year or so, I've been within lip-to-cheek distance of Alec Baldwin, Jennifer Garner, Arnold Schwarzenegger, Annie Lennox, Jude Law -- not even Gary Coleman tried anything. Thank God for rules.)

Once in a while someone rebels on religious grounds or other principles. At one of those Washington tuxedo-and-evening-gown dinners this spring, a man complained to me that a female acquaintance refused to kiss him hello on the cheek. That everyone thought it was a little rude of her is just another indication of how Hollywood we've all gone.

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