Listen up, students of love, today’s lesson is on philematology — the science of kissing. When was the last time you put serious thought into your kissing technique? High school? Instead of trying to master a new position from the Kama Sutra, remaster the first step of foreplay – the kiss.

Though most of us happily smooch our lovers, friends and family without second thought, when you give it some consideration, sticking your tongue into someone’s mouth – full of all those germs – doesn’t really seem like a natural way to express affection. And it isn’t a natural behavior, technically. Kissing – osculating, if you want to take this science thing seriously – is a learned action, not an instinctual one. In fact, there are still many cultures where kissing just doesn’t happen (joyless places, we can all agree).

So how did we kissing fools pick up the habit? Anthropology’s best guess is that kissing’s roots go back to a time long ago when mothers chewed their food and passed it by mouth to their young children. From there it became a sign of comfort or affection between mother and child, and later, in other relationships. Another popular – and more romantic – -theory is that kissing developed as a gesture symbolizing the union of souls. The Inuit, for example, believe the exhaled breath is part of the spirit, so rubbing noses (“Eskimo kisses”) is a way for your souls to mingle.

Like most human behavior, though, kissing can be explained by simple biology. Kissing, flirting, and of course, sex, are all related to pheromones. When you’re lip-to-lip, you’re close enough to subconsciously pick up on the hormone cocktail wafting off the scent glands on your partner’s cheeks. Women swoon for signals that the male has proper immunology to create a healthy child, while men pick up on signs of the woman’s fertility and strength. And all this time you thought you were just kissing because it felt good! Well, that’s part of the kissing equation, too. Our lips and tongues are packed with nerve endings, and the right stimulation increases your pulse and blood pressure, quickening the speed in which your brain starts pumping out the chemicals that make you feel all weak-kneed and googly-eyed.

But sometimes a kiss is just a kiss. There are all kinds of reasons for kissing, and not all of them have to do with sex. There’s the just-friends kiss, the good-bye kiss, the sympathy kiss, the kiss-and-make-up kiss, the good morning, sorry-I-haven’t-brushed-my-teeth kiss and millions more we haven’t even thought of. And that’s good. Since the average person spends two weeks of their life kissing, you’ve got plenty of time to try them all.

If you can’t kiss well, why should your lover believe you could do anything else? Here are a few techniques:

Begin with an Eskimo kiss: Make full body contact. Rub the side of your lover’s nose against your nose using small circles. Sound childish? Not according to Judith Jackson, author of Scentual Touch. She says, “The nose is lined with tissue very similar to the erectile tissue in sexual organs.”

Touch your lover’s face: Don’t feel his/her face like you’re blind. Rather gently place your fingertips on his/her chin or behind one ear. Don’t pull her towards you. Lean towards him/her until your lips meet.

Lock lips: Don’t try to impress him/her with your cultural understanding of the French by sticking your tongue in his/her mouth. Part your lips, and press your lips against his/her lips.

Get tongue-tied: Circle the tip of his/her tongue with yours. Kissing is a two way street. Let his/her tongue into your mouth as well.

Don’t swap too much spit: Consider the game over if he/she has to wipe his/her chin. Salivate over steak, not a woman/man.

A kiss isn’t just a kiss. Your kissing technique determines where else the night will lead.