Each of us has a protected zone two or three feet wide, swelling around the head and narrowing towards the feet. This zone isn't fixed in size: if you're nervous, it grows; if you're relaxed, it shrinks. It also depends on your cultural upbringing. Personal space is small in Japan and large in Australia. This safety zone, called personal space, provides an invisible spatial scaffold that frames our social interactions. As Michael Graziano argues...