What is "invisibilia"

Invisibilia is a radio program and podcast produced and hosted by Alix Spiegel, Lulu Miller, and Hanna Rosin for National Public Radio. The show began its first season in early 2015, and "explores the intangible forces that shape human behavior—things like ideas, beliefs, assumptions and emotions." The program's title comes from Latin, meaning "all the invisible things". The Guardian ranked Invisibilia among "the 10 best new podcasts of 2015."