The poet, essayist, and novelist Charles Baxter started his career in 1984 with an award-winning collection of short fiction. Many accomplished books later, Baxter has chosen twenty-three outstanding stories for Gryphon (Vintage, $16). The typical Baxter character falls somewhat short of heroism; like many of the ordinary, complex figures in Chekhov’s work (which one of Baxter’s characters recommends), they’re diligent, middle-class people, the type who might get “carefully drunk” a little too early in the day, or who want to make a difference by, say, helping the homeless, but whose good intentions backfire. Earnest and compassionate in his depictions of an uncle adopting his dead brother’s son, or a young couple testing themselves by driving across a frozen lake, Baxter also has a delightfully whimsical side. In the title story, more reminiscent of Lewis Carroll than of Chekhov, a fourth-grade class goes slightly down the rabbit hole when a substitute teacher shows up with “substitute facts,” declaring that “sometimes” six-times-eleven could be sixty-eight.