What's behind this wall? As I write, here in my surgeon's study, I ask myself that question. What's behind it? My neighbors? Then what do I know—really know—of them? After all, this wall which rises beyond my desk, the wall against which my glass case of instruments rests, symbolizes the boundary of knowledge—seemingly an opaque barrier. I am called a man of science, a man with a passion for accuracies. I seek to define a part of the limitless and undefined mysteries of the body. But what is behind the wall? Are we sensitive to it? You smile. Give your attention then to a narrative of facts.