“The death of a parent, he wrote, “despite our preparation, indeed, despite our age, dislodges things deep in us, sets off reactions that surprise us and that may cut free memories and feelings that we had thought gone to ground long ago. We might, in that indeterminate period they call mourning, be in a submarine, silent on the ocean’s bed, aware of the depth charges, now near and now far, buffeting us with recollections.”