When I was young, my mother showed me an educational book that had things like riddles, puzzles, and mental exercises in it. One of these entries had a short, mundane paragraph, followed by some form of "what was wrong with that text?"

It then explained that I had missed the word "the" being on the end of one line but also the start of the next line which, indeed, I did miss. It suggested that the human mind couldn't see duplicate words split in such a way, at least in English, unless actively looking for them.

I now know that, while it did trick me, its theory was incorrect ... Because I can't not see "from from."