How close is too close for comfort? Most people would take a step back from someone who leans in too close. Fascinated by how people perceive and react to space, a man developed spent years studying it and improving on it.

Vox’ video on proxemics explains how Edward T Hall of the Illinois Institute of Technology developed a shorthand specially to study personal space. His ideas on the personal space bubble are still being used in a number of other disciplines to understand how we interact with the world.

Watch the video here: