In The Rationalist’s Guide to the Galaxy, Tom Chivers went ‘native’ in San Francisco’s self-named ‘rationalist’ community. One of the anecdotes he reports about his adventures there involves a young woman rationalist who toted around a robot baby (or what your five-year-old would call a ‘doll’) that cried, and required attention and nappy changes and other such things.

She, in all seriousness, explained that she was doing this to find out if she was ready to have a real baby.