The Irish poet and philosopher John O’Donohue was beloved for his book Anam Ċara, Gaelic for “soul friend,” and for his insistence on beauty as a human calling. In one of his last interviews before his death in 2008, he articulated a Celtic imagination about how the material and the spiritual — the visible and the invisible — intertwine in human experience. His voice and writings continue to bring ancient mystical wisdom to modern confusions and longings.