There are a dozen reasons you might want to go digging around somebody else’s land with a shovel and a vaguely communicated purpose. If so, spare some hassle and call yourself an “archaeologist.”

You can still dink around with a garden trowel in someone’s petunia garden if you want, but uppity neighbors might accuse you of trespassing, or possibly grave robbing, if you happen to wander too far. That’s why it’s best to grow a beard and call yourself an “excavator.”

I have first-hand knowledge of archaeology because I once studied it at Brasenose College, Oxford. While an undergraduate student I took full advantage of our Honors at Oxford program to study abroad. I chose “England” because I was too lazy to bother learning French, and also because I had once seen a postcard from Berkshire which had a picture of a castle on it.

My friend Evan and I enrolled in an Archaeology course because we thought there was a higher chance of inadvertently discovering buried treasure than in any of the other offered classes focused on analyzing poetry by dead people. Whereas the Literature courses involved “books,” which seemed like a lot of work and were probably flammable, Archaeology used these things called “shovels.” Evan considered himself something of a shovel aficionado qua his Red State upbringing, and I had once employed one to kill a gopher. We were set!

Each school week Evan and I would attend classes and try to sober up. Much to our surprise Archaeology also had books, very little of which dealt with shovel maintenance. Every once in a while, if we promised to be on our best behavior, our tutor permitted Evan and I to join her and other professional archaeologists on “a dig.”

“Digs” are what graduate students call “treasure hunting” to confuse the farmers whose land they’re plowing through looking for gold. Nobody ever tells the farmers that they’re looking for swag, because the farmers would say “Hey, I want some of that gold!” if the archaeologists found any. Then the British Ministry of Agriculture would get called in to make sure there wasn’t too much gold laying around to ruin the topsoil or confuse raccoons, and the whole project would get mired down in one giant orgy of English bureaucracy.

So to make things simple we would just lie to the farmers and tell them we were looking for broken bits of Roman pottery, or obsolete Walkman headsets leftover by the Vikings. We even brought little toothbrushes with us, just to confuse the locals. The farmers would stand around, hands on hips, wondering what the hell we were doing out in their barley fields with dental supplies and gardening equipment. Meanwhile, we would quietly prod the earth in search of bullion or oysters. (Pearls, a form of treasure, come from oysters.)

I never wound up finding any actual gold. Mostly just bits of useless old Roman pottery, which I threw away. The only truly exciting moment during a dig was the time I found some pig teeth. I mistook them for human incisors and then promptly and loudly accused the nearest farmer of murder.

Fortunately the other archaeologists had encountered pig molars before, or had possibly committed murder themselves, so they could tell the difference between the two and we all had a good laugh. That is, until the British Ministry of Agriculture got involved. After that everyone had to fill out a lot of paper work.

This is all a very roundabout way of saying that most everything we know of ancient human society comes from the crap people accidentally left behind. Half the stuff we know about the Carthaginians and Egyptians and Minnesotans are from the piles of garbage which collected under their windows, only to eventually be exhumed by disappointed treasure hunters looking for jewels. Imagine cobbling together an understanding of twenty-first century culture purely by the contents of its dumpsters. That’s archaeology.

History itself comes from only three sources: propaganda, correspondence, and junk people left behind. We officially call propaganda “history”, to signify that academics have organized heavily biased press releases into a coherent, chronological order.

Our final insight comes from correspondence. Most of what we know about 18th century life comes from love letters, IOU notes and death threats. (And of course the pig teeth we dig up.) The modern equivalent of correspondence is Facebook, Twitter and e-mail.

Think about that next time you post an emoticon about your latest dinner. Future historians will one day comb through our digital leftovers and analyze our century based on memes of funny cats.

Does that bother me? No. I write long, rambling blog posts myself. Plus (and this is the important thing) they will never find my gold.