How do you know that you don’t know what you don’t know?
It’s an interesting problem that we all wrestle with. There really are things that are so hidden that you don’t know what you are missing.
The problem is that there are some who want to keep you from finding out what you don’t know. And, the first place that they start is the index to the Internet.
If they delete information from a search engine, it is impossible to find out what you don’t know. They call that a memory hole.
They just did that to one of my articles.