"You know," I said, "I kind of like your word geas. Because that's exactly what it seems to be—a geas. A hex, an enchantment, if you wish.
"Did you know that Brownlee was an anthropologist before he turned to psychology? He has some very interesting stories to tell about hexes and so on."
"I'll have to hear them one day." His Grace took a pack of cigarettes from his pocket. "Cigarette?"
"No, thanks. I gave up smoking a few years back."
He puffed his alight. "This geas," he said, "reminds me of the fact that, before the medical profession came up with antibiotics that would destroy the microorganisms that cause gas gangrene, amputation was the only method of preventing the death of the patient. It was crippling, but necessary."
"No!" My voice must have been a little too sharp, because he raised one eyebrow. "The analogy," I went on in a quieter tone, "isn't good because it gives a distorted picture. Look, Your Grace, you know what's done to keep a captive wild duck from flying away?"
"One wing is clipped."
"Right. Certain of the feathers are trimmed, which throws the duck off balance every time he tries to fly. He's crippled, right? But if you clip the other wing, what happens? He's in balance again. He can't fly as well as he could before his wings were clipped—but he can fly!
"That's what Brownlee's geas does—restore the balance by clipping the other wing."