In trendy places like Brooklyn and Silicon Valley, the drug of the moment is ayahuasca: a psychedelic brew that makes its users vomit, cry, envision their deaths, and, occasionally, even attain enlightenment. The New Yorker staff writer Ariel Levy investigates the hallucinogen. Jenny Allen seeks enlightenment, too, in the form of compassion for her obnoxious co-workers. She recites gathas for modern mindfulness. Plus, David Remnick talks politics and sports with the N.B.A.’s all-time leading scorer, Kareem Abdul-Jabbar, who has reinvented himself as a writer.