It sounds like he’s talking about the premise that a lot of human innovation has been built off of applying concepts from one area to another.

I haven’t read The Importance of being Educable, but I have read Range and thought it was a reasonably good presentation of the idea that broadening your base of knowledge and allowing yourself to take inspiration from unrelated fields to solve problems has value. That seems to be the core concept of the article, and presumably the book. That being able to take new ideas from old experiences is a big part of solving problems.