In their talk at Cave Canem on May 19, “The Spirit That Is Charged: A Conversation about Poetry and Friendship,” Tina Chang and Tracy K. Smith offered a glimpse into their 20-plus years of friendship, sharing anecdotes and letters from their days as MFA students at Columbia and speaking with candor about writing, marriage, parenthood, aging, loss, and more-not to mention their shared love of music and karaoke.