I got to go to the Iowa State Fair on Sunday and eat a very excellent pork chop on a stick as I stood by the U.S. Marines booth, where various civilians lined up to do chin-ups on a high bar, counted off by a Marine whose T-shirt said "Pain Is Weakness Leaving The Body." I've seen many things at state fairs but never chin-ups. The look of chagrin on men's faces who had believed they could do chin-ups and then the truth dawned on them. One man looked as if he might blow out his aorta. A small, sharp memory of high school phy-ed. I had to turn away.

I passed up the novelty foods, the deep-fried pineapple on a stick, etc. A fair isn't about food, it is a carnival of ideas where the Lutheran booth sits between the "reverse osmosis" water purifier booth and the hot-tub booth. Here is an 8-foot-by-8-foot tub that seats four and reclines one, with water jets and a pedestal table for your champagne, which would feel awfully good after a day of combining. Redemption By Faith Alone versus Creaturely Comfort. Nearby you can learn about ethanol and hear the horn of a Model T, which sounds like a terrified goose, or you can talk to a lawyer at the bar association booth. (He told me that most questions are about leases or divorces.)

Most fairgoers walk past like stunned sheep, but men are waiting in booths who'd be glad to explain about corn yield and herbicide or Republican principles or the advantages of vinyl siding. A kindly salesman told me all about an infrared "health cabin," which is sort of a sauna but without steam, just heat, up to 140 degrees, which "aids in the relief of chronic fatigue" and will detoxify you and "balance" your blood pressure. I didn't buy one, but I enjoyed the pitch. Salesmanship is basically a civil and amiable profession. Fifty feet away are the Methodists (Find Your Path, Share The Journey) and a display of bottled water (zero calories). And the anti-abortion people, and the natural latex mattress booth (80 percent less tossing and turning), and a booth selling a GPS gizmo that provides weather info and also local movie times.

The beauty of a fair is conversation. You walk up to the Methodists and say, "What does that mean, 'find your path'? Is there more than one?" and you're good for 15 minutes. Talk, talk, talk, everywhere. Witness the rare art of barking, which is the art of rising inflection, and here is a crowd of overheated people in shorts and sneakers watching a green pepper being sliced and minced by a barker who made it seem thrilling. And next door, the hysteria of the auction ring, the old man in the big white hat and his bidibidibeebidy ululation, the shouts of his spotters, the old man hollering "Here we go!" and "It's only money! It'll only hurt for a little while!" and then "Sold for fifteen hundred dollars!"

I saw acres of machinery where a man who took a wrong turn into the liberal arts can contemplate a life he'll never live and stuff he'll never own. A beautiful 29-foot flatbed trailer with pine flooring on which you could carry hay bales or a tractor. A 4-by-4 double-cab pickup you could pull your trailer with. And beyond it an acre of FFA-restored tractors that put an older Midwesterner in a very thoughtful mood. The green John Deeres and Olivers, the red Farmall and Allis-Chalmers, the yellow Minneapolis Moline. The steel bucket seats on a coiled spring, the exhaust stacks, the brake and clutch pedals. You could climb up in that seat and be 14 again. I was happy back then pulling a manure spreader across the corn stubble on a September day, big clots of matter flying through the air. I miss those days.

And then I wound up at an open-air brick pavilion for the llama judging. Llamas are gentle, dignified beasts, and here were four of them being shown by teenagers. The animals' military bearing, heads high, their stately gait, their dark soulful eyes — they looked as if they'd walked straight out of "Dr. Doolittle," and it was sweet to see them being handled lovingly by teenagers. Pigs are something else — you can see how a person might need to whack a pig. But nobody would ever whack a llama. According to a poster, they are raised for "fiber, showing, carting, guardians, and companionship." One girl stood by her llama and blew gently on its nose, and he looked lovingly into her eyes. A sort of conversation. If every teenager had his or her own llama, this would be a very different country.

Garrison Keillor's "A Prairie Home Companion" airs from 6 to 8 p.m., on Saturdays on KHPR FM 88.1 and on Sundays on KIPO FM 89.3 His column appears Wednesday at http://honoluluadvertiser.com/opinion and in Sunday's Focus section.