Stavanger Bay life is like a box of chocolates

Infinity is a novel concept to Aesop, apparently.

Though he thought his knowledge far-reaching, it was limited greatly. If his knowledge was infinitely increasing, then so too was the limit of knowledge to learn. Aesop would probably shit himself if he knew what Chemistry was. Alas, the canine mind can only accomplish so much, and while he was a great thinker, he was still limited. "I know star lore, yeah," he said, shrugging, "didn't think you were the type, but I guess I got you pegged wrong. What d'you know so far?"

Charon was clearly far more interested in the stars than in swimming (and honestly, Aesop couldn't blame him.) "But swimmin' shit ain't fun to learn in the winter. Water's cold n'all. I'll make good on my promise in the spring, if you remind me." That provided them both an out, at the very least. Unless he was truly fervent about learning to swim, Charon would probably forget, and then Aesop would get out of teaching swimming lessons. And if Charon did remember, it would only be because it was important to him.