We, the reader, just eavesdrop. I hear Socrates, too. They are not obvious doppelgängers, these two. Centuries separate them. Thoreau wrote more than two million words, Socrates not a single one. Yet they are philosophical brothers. Like Socrates, Thoreau led an examined life, one conducted with a “fearless self-inspection.” Like Socrates, Thoreau vacillated between terrific velocity and utter stillness. He walked four miles a day but could also, as one neighbor recalls, “sit motionless for hours, and let the mice crawl over him and eat cheese out of his hand.”