It turned out that somehow, my career up to that time had turned me into exactly the sort of expert that World Book felt comfortable badgering. They didn't think I was the most important virtual reality expert in the world.

That person was too busy for them to approach. But me, I was in that midrange level – just respectable enough … but not so famous that I'd turn them down.

" Would you like to write our new entry on virtual reality? " they asked. I couldn't tell them that I'd been waiting all my life for this call.

All I could say was, " Yes, of course! " I wrote the entry. And I included a photo of my student Caitlin Kelleher wearing a virtual reality headset.

No editor ever questioned what I wrote, but I assume that's the World Book way. They pick an expert and trust that the expert won't abuse the privilege.

I have not bought the latest set of World Books. In fact, having been selected to be an author in the World Book, I now believe that Wikipedia is a perfectly fine source for your information, because I know what the quality control is for real encyclopedias.

But sometimes when I'm in a library with the kids, I still can't resist looking under " V" (" Virtual Reality" by yours truly) and letting them have a look. Their dad made it.