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New Year’s Eve: a time for drinking, partying and imagery and activities focused on kissing. Lots of kissing. The New Year’s kiss is an age-old tradition (literally, it may go back to the Iron Age). And at this point, it is so ingrained in our popular consciousness that no one gives much thought as to why we do it. Part of the reason we don’t think much about the “why” is probably because we've had a lot of Champagne by the time the subject springs to mind around 11:51 p.m. every Dec. 31. But there are several theories about why we lock lips at the end of every year, so take your pick. An interesting story may help seal a last-minute smooch.

1. Because the Romans. The Romans, in their never-ending love of debauchery, hosted an annual festival in December called Saturnalia to celebrate the coming of the new year. As with many Roman festivals, there was much touching of lips and various other body parts. Some scholars attribute today’s much more demure kissing custom to that.

2. To ward off loneliness. According to the Encyclopedia of Superstitions, there is a long-standing notion of unknown origins that  if you are single and don’t kiss someone—anyone—on New Year’s Eve, you will have an entire year of loneliness. It’s like your love life just walked under a ladder.

3. To get closer to your special someone. According to English and German superstition, kissing the one you love at midnight will ensure an entire year of affection from them.

4. To be close to a new special someone. Those same superstitions hold that you will have a special relationship with the very first person you kiss in the new year. Hopefully you believe in love at first tongue.

5. To rid yourself of evil spirits. It seems like evil spirits are at the heart of most good traditions. For hundreds of years, Europeans held masquerade balls for holidays, including New Year’s. Masks symbolized evil spirits, and a kiss following the mask’s removal symbolized purification.

6. To blur the line between friends and strangers. In Scotland, the New Year’s celebration is called Hogmanay. According to tradition, you should show hospitality to friends and strangers alike in the new year. That’s why it’s customary to kiss every single person in the room with you. If you've been especially lonely this year, you might want to consider a last-minute booking to Edinburgh.