Many years ago, when I was a newspaper reporter, I did a story on autism. At that time (late 1970s, early 1980s) the condition was defined very differently than it is today. Among other things, autistic children didn’t make eye contact, didn’t respond appropriately when spoken to and were unable to function. The condition was obvious from infancy, when such children didn’t even smile at their parents. For my story, I visited a small group home for autistic adults. Meaningful communication with them was not possible. Today, I see articles asking why the number of children with autism has increased so drastically. To me the answer is simple: the definition of autism has expanded to include all sorts of behavior that would never have been considered autistic decades ago. In this way, a very rare condition has become a relatively common one.