Genny

Genny worked at the deepest desk in the workshop, the one solvers wandered to when they'd already solved something and felt a curious itch to understand why it worked — and Genny fed that itch with one irresistible question: "That's the answer for these numbers. What's the rule for any numbers?"

When a solver triumphantly reported "3 chickens and 5 cows!", Genny would nod and then lean in. "Beautiful. Now — what if it were 10 heads and 34 legs? Or 20 heads and 50 legs? Could you find a rule that spits out the answer for whatever heads and legs someone throws at you?" And Genny would help them build it: if you had all chickens, you'd have 2 legs per head; every cow you swap in adds 2 more legs; so the number of cows is (the legs you have, minus 2-per-head) divided by 2. "One rule," Genny said, "and now you've solved not this riddle — you've solved every riddle shaped like it, forever. Solve the one, then reach for the all."

Genny caught the generalizing itch from a solved problem that felt incomplete.

As a young solver, Genny solved a riddle correctly and felt, oddly, unsatisfied — because the very next riddle was the same shape with different numbers, and Genny had to start all over. "It feels like I keep re-solving the same problem," Genny complained. "You do," said Cass, delighted, "which means there's a rule hiding under all of them, and you're the sort of person who wants it. So find it. Solve one carefully, watch which steps depended on the specific numbers and which didn't, and replace the specific numbers with names. What's left is the rule for the whole family." The first time Genny wrote a rule that solved a hundred riddles at once, it felt like being handed a skeleton key. "Don't just answer the question," Cass said. "Answer its whole family."

When the kid arrived, freshly proud of solving the chickens-and-cows riddle, Genny gave them the itch on purpose.

"3 and 5 — lovely. But suppose I change the numbers tomorrow. Do you want to start from scratch, or do you want a rule that never makes you start from scratch again?" The kid, intrigued, chose the rule. "Then let's watch what you just did, and notice which parts cared about the specific 8 and 26, and which parts would work for any heads and legs..." Together they traced it and replaced 8 with "H" and 26 with "L," and out fell a little rule that took any H and any L and returned the animals.