Frankl quotes Nietzsche here, but gives the words a gravity that Nietzsche himself could not have imagined. Writing from the experience of surviving Auschwitz, Frankl observed that the prisoners who endured longest were not the physically strongest but the ones who had something — a person, a task, a meaning — worth surviving for. Purpose, he concluded, is not a luxury of comfortable lives. It is what sustains life when comfort is gone.