"Just grab a shirt and let's go," my girlfriend said.

But I hesitated. We were going whitewater rafting with her mother, and the top T-shirt in my drawer proclaimed its wearer an "Uneducated Idiot." Somehow it didn't seem a wise message.

The moment has resonated with me, in part because I live near Yellowstone National Park, which is like grad school for T-shirt scholars. The question that drives my research: How do people select a shirt to wear? Is it, "OK, we're in the mountains, so I need 'Vail' not 'Cancun'"?

T-shirts are a vacation phenomenon. Most people don't wear them to the office. But for some reason, vacationers always wear T-shirts from some place else. In Yellowstone, people buy T-shirts that say "Yellowstone National Park" on them, but they won't wear them until they get out of the park. The way I figure it, at any given location, the recreation of people on vacation is to buy T-shirts to wear on their next vacations.

I've also been thinking about the way they're made. When you say "T-shirt," most people think of the stereotype: cheaply produced and boasting a dumb saying, like the "I'm with Stupid" T-shirts of the 1970s (and I'll admit, in junior high school I thought those were pretty funny). But in the last 20 years, we've seen increasingly sophisticated T-shirts.

Call it the Lands End factor. "We use 100 percent ringspun combed cotton (the softer, stronger kind) in a substantial jersey knit," says the famously overwritten clothing catalog, also discussing "premium ink," "covered seams," and a "generous cut." About a T-shirt!

These fancier T-shirts generally have more subtle messages. After all, they can't say "My relatives went to Yellowstone, and all I got was this $35 ringspun combed cotton jersey knit softer, stronger kind of shirt." No, an expensive shirt just says "Yellowstone" or preferably someplace more obscure, such as "McGuffin's Flyfishing Lodge."

But again, you never wear the McGuffin's T-shirt to McGuffin's. You wear it to Sun Valley or Santa Fe, where it advertises the fact that your previous vacation was at someplace more obscure and exclusive. At McGuffin's, you wear a T-shirt from a helicopter-skiing resort in the northeastern Yukon. And in the Yukon -- luckily for you or else the addiction would get prohibitively expensive -- it's too cold to wear T-shirts.

I'm something of a rebel against this societal striving (either that, or I'm something of a cheapskate): I prefer a free "County Fun Run" sort of T-shirt.

This, however, led to my problem the day of the rafting trip. My Boys and Girls Club T-shirt and county basketball tournament T-shirt were in the wash. My fun-run T-shirt clashed with my shorts. Since my girlfriend's mother doesn't drink, I didn't want to wear T-shirts given out by my favorite taverns and microbreweries. My Society of American Foresters T-shirt (received for speaking to a regional meeting) was too threadbare, and my High Country News T-shirt (a bonus for writing articles like this one) was the one I'd been wearing the last time I met the woman.

That left just the "Uneducated Idiot" T-shirt, which I’d received for participating in an odd if entertaining political battle: A developer had said that the only people who opposed his project were "uneducated idiots." So an over-educated opponent took the slur as a point of pride and printed up shirts repeating it. Still, I've learned that I get lots of strange looks when I wear that shirt out of town.

What would I have given at that moment for a $35 McGuffin Flyfishing Lodge T-shirt! I was ready to spend thousands of dollars on a vacation, the purpose of which would be to buy some better shirts to wear to the next family weekend. Then I remembered a different approach, revealed during a visit last summer from my friend Steve, a Wall Street accountant. He spent his entire vacation wearing a T-shirt with an unexplained acronym that was something like SSECA.

Finally I asked him, "What's SSECA?" I imagined it being something like the Symposium on Standards and Ethics in Corporate Accounting, an effort to show that his last trip had been someplace more obscure and exclusive than Yellowstone.

"Huh?"

"Your shirt!"

"Oh, I don't know," he said. "I just grabbed whatever was on top in the drawer."

John Clayton is a contributor to Writers on the Range, a service of High Country News in Paonia, Colorado (hcn.org). He writes in Red Lodge, Montana.