Kang Junu's home. It was Sunday afternoon, and the living room was quiet.

Unmelted snow still lay outside, and a faint wisp of steam rose from the coffee on the table.

Go Mihui turned a page of the book she was reading and looked at her son across from her.

Since his admission to Seoguk University's business school was confirmed, Kang Junu had been reading a lot more.

And he'd been going out less since coming back from St Moritz.

He'd read a business book, then open a book of philosophy, and copy the passages he didn't understand into a notebook.

He no longer moved straight on to the next page the moment his curiosity was satisfied, the way he used to.

Just today, he'd been staring at the same page for a long time.

"Is it hard going?"

Go Mihui asked, picking up her coffee cup.

"The sentences aren't hard. It's hard to agree with."

"Which part?"

"The part about people making rational choices in their own interest."

Kang Junu slipped a finger into the book to keep his place and looked up.

"There are people who dig in out of pride even when they know it'll cost them."

"For that person, protecting his pride might be the bigger interest."

He thought for a moment, then nodded.

"So what I think of as someone's interest and what they think it is can be different."

"Exactly. If you decide someone's a fool before you know why they chose what they did, you miss what matters."

Go Mihui looked at the notebook her son had left open. It was crammed with short questions.

They asked what problems money couldn't solve, and when authority and responsibility came apart.

Somewhere along the way, her son had grown up enough to wonder about the deeper meaning of things.

"You've been thinking a lot since you got back from St Moritz."

"I found out I don't know as much as I thought."

Kang Junu said it plainly, as if he'd already sorted it out for himself.

"Leave out my family, and there wasn't much I…