A sheep farmer is tending his flock when a city slicker rolls up in his BMW, hops out and asks, "Hey, if I tell you exactly how many sheep you have, can I take one?" The farmer nods, so the city slicker opens his laptop, calls up some satellite photos, runs some algorithms, and announces, "You have 1,432 sheep."
Impressed, the farmer says, "You're right. Go ahead and take one." So the city slicker loads one of the animals into the backseat of the car. "Now," says the farmer, "I'll bet all my sheep against your car that I can tell you what you do for a living."
A gaming sort, the city slicker says, "Sure."
"You're a consultant," says the farmer.
"Wow!" says the consultant. "How'd you know?"
"Well," says the farmer, "you come from nowhere even though I never asked you to. You drive a flash car, and wear a smart suit. You told me something I already knew. And you don't know anything about my business. Now give me back my dog."