You step onto an airport's moving walkway, a flat metal conveyor belt that conveys travelers down an airport concourse, sparing them the indignity of burning a few calories by walking a bit. And soon a recorded voice says: "The moving sidewalk is coming to an end. Please look down."

Well, yes. Pretty much everything does come to an end, doesn't it? Besides, we can actually see what we already knew — the moving walkway does not go on forever. So, is that announcement about it ending really necessary? Whatever happened to the rule, "Do not speak unless you can improve the silence"?

Passing through an American airport is an immersion in a merciless river of words. They are intended to be helpful but clearly they flow from an assumption that increasingly animates our government in its transactions with us. The assumption is that we are all infants or imbeciles in need of constant kindly supervision and nudging, lest we allow ourselves to be flung off a moving walkway and over the edge of the world.