Why are there no chairs in the Bible, or in all 30,000 lines of Homer? Neither are there any in Shakespeare’s Hamlet – written in 1599. But by the middle of the 19th century, it is a completely different story. Charles Dickens’s Bleak House suddenly has 187 of them. What changed? With sitting being called “the new smoking”, we all know that spending too much time in chairs is bad for us. Not only are they unhealthy, but like air pollution, they are becoming almost impossible for modern humans to avoid.