After repeatedly failing to find a room on the campus of Carnegie Mellon that is silent enough to record our podcast in, we asked ourselves this question. Because every little sound messing up our pristine recording—the spinning of computer fans, the constancy of indoor climate control, the buzz of traffic filtering in from outside—seemed to be a product of the modern age. Was the world a more silent place 100 years ago? We pursue the answer by talking with an author who wrote a book about trying to find silence in, of all places, Manhattan. Along the way we encounter the world's quietest place, a rare condition where everyday sounds can cause anxiety and even madness, and ask the bigger question: "what IS sound?" Because we didn't really know. image credit: flickr user hebedesign