Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Humorous, Upbeat
This is a feel-good book. There are laughs to be had reading about quirky Socrates, there's inspiration to be found in Dan overcoming his leg injury and finding unreasonable happiness, and there's even a love story ending in a marriage.
Even the depths of philosophical paradoxes plumbed by Socrates and Dan can't bring down the upbeat tone. If it gets complicated, one or the both of them will crack a joke, and, even if they don't the ultimate message is: Don't Worry Be Happy.