Father shrugged. “I know everything.”
“A certain teacher once told me that the only truly stupid man is the one who doesn’t know he’s ignorant.” Rigg loved this game, partly because Father eventually got impatient with it and told him to shut up, which would mean Rigg had won.
“I know that I know everything because there are no questions to which I don’t know the answer.”
“Excellent,” said Rigg. “So answer this question: Do you know the answers to the questions you haven’t thought of yet?”
“I’ve thought of all the questions,” said Father.
“That only means you’ve stopped trying to think of new ones.”
“There are no new questions.”
“Father, what will I ask you next?”
Father huffed. “All questions about the future are moot. I know all the answers that are knowable.”
“That’s what I thought. Your claim to know everything was empty brag.”
“Careful how you speak to your father and teacher.”
“I chose my words with the utmost precision,” said Rigg, echoing a phrase that Father often used. “Information only matters if it helps us make correct guesses about the future.” Rigg ran into a low-hanging branch. This happened rather often. He had to keep his gaze upward, because the pench had moved from branch to branch. “The pench crossed the stream,” he said. Then he clambered down the bank.
Vaulting over a stream did not interrupt the conversation. “Since you can’t know which information you’ll need in the future, you need to know everything about the past. Which I do,” said Father.
“You know all the kinds of weather you’ve seen,” said Rigg, “but it doesn’t mean you know what weather we’ll have next week, or if there’ll be a kind of weather you never saw before. I think you’re very nearly as ignorant as I am.”
“Shut up,” said Father.
I win, said Rigg silently.
A few minutes later, the trail of the pench went up into the air and kept going out of sight. “An eagle got him,” Rigg said sadly. “It happened before we even started following his path. It was in the past, so no doubt you knew it all along.”
Father didn’t bother to answer, but let Rigg lead them back up the bank and through the woods to where Rigg first spotted the pench’s trail. “You know how to lay the traps almost as well as I do,” said Father. “So you go do it, and then come find me.”
“I can’t find you,” said Rigg. “You know I can’t.”
“I don’t know any such thing, because no one can know a false thing, one can only believe it with certainty until it is contradicted.”
“I can’t see your path,” said Rigg, “because you’re my father.”
“It’s true that I’m your father, and it’s true you can’t see my path, but why do you assume that there’s a causal connection between them?”
“Well, it can’t go the other way—you can’t be my father because I can’t see your path.”
“Do you have any other fathers?”
“No.”
“Do you know of any other pathfinder like you?”
“No.”
“Therefore you can’t test to see if you can’t see the paths of your other fathers, because you don’t have any. And you can’t ask other pathfinders whether they can find their fathers’ paths, because you don’t know any. So you have no evidence one way or another about what causes you not to be able to see my path.”
“Can I go to bed now?” asked Rigg. “I’m already too tired to go on.”
“Poor feeble brain,” said Father. “But how it could wear out I don’t know, considering you don’t use it. How will you find me? By following my path with your eyes and your brain instead of this extraordinary ability of yours. You’ll see where I leave footprints, where I break branches.”