For thousands of years, humans have sought to develop the ideal seat, from the Song dynasty yokeback (one of the earliest uses of lumbar support) to the modern ergonomic desk chair. In his new book, Now I Sit Me Down: From Klismos to Plastic Chair: A Natural History, architect Witold Rybczynski argues that the search will never end–because humans aren’t built to sit. “We are good at walking and running, and we are happy lying down,” he writes. “It is the in-between position that is the problem.” Some seats are more helpful than others: the rocking chair famously helped alleviate President Kennedy’s back issues, and the invention of the dentist chair made it easier to treat cavities. In the future, Rybczynski writes, humans may well invent a chaiselike seat designed around browsing a smartphone. The only constant with chairs, he concludes, is that they will keep evolving.
This appears in the August 29, 2016 issue of TIME.