Some people can predict what people are going to say (more like "from nothing", not like completing someone else's sentence), or what they are thinking. That's where this idea comes from.
I think it won't happen for no reason, there must be some signals from the human body, and some people can react to such signals (predict).
Imagine the possibilities if we could detect those signals and convert them to words or text.
Please contact me if you are interested.
My email: firstname.lastname@example.org